Questions and answers by visitors named Lisa


  1. How did Drs. Peter and Mary Grant verify Darwin’s theory of natural selection?(1 point)

    by studying a different group of organisms by assessing changes in another animal trait by finding new species that adapted to a different environment by making

  2. Please check my answers!

    How are the governments of jordan and kuwait different from the governments of the united Arab Emirates and oman? A. Citizens of jordan and kuwait can vote. B. Jordan and kuwait have monarchs**** C. The king of jordan and emir of

  3. In what present day countries can the sites of your civilizations be found? Help asap! I will thank you so much if you answer this question before 5:00 pm tonight! Thank you! Have a terrific day/thanksgiving break!

  4. What is 66 2/3% of 891?

    PLEASE show me the steps on how you got the answer to this question...

  5. The force needed to keep a car from skidding on a curve varies inversely as the radius of the curve and jointly as the weight of the car and the square of the car's speed.Suppose that 400 pounds of force keeps a 1600-pound car from skidding on a curve of

  6. 38. Which of the following sentences contains a helping verb? (1 point)

    Eduardo looked in the basement, but the puppy wasn’t there. Sakkom hung wind chimes because she loves the sound. Roger has never performed a solo in his life. The leader of the troop

  7. How much heat, in kilojoules, is associated with the production of 273kg of slaked lime, Ca(OH)2?

    CaO(s)+H2O(l)-->Ca(OH)2(s) delta H=-65.2kJ

  8. Linear Functions Unit Portfolio

    Directions: Complete each of the tasks outlined below. Cab companies often charge a flat fee for picking someone up and then charge an additional fee per mile driven. Pick a U.S. city and research the rates of two different

  9. A 5 gram sample of a hydrate of BaCL2 was heated, and only 4.3g of the anhydrous salt remained. What percentage of water was in the hydrate?

  10. What was Thomas Jefferson's stance on the Declaration of Independence?

    What is a pro and con of the Declaration of Independence Please Help Me

  11. A woman drove to work at an average speed of 40 miles per hour and returned along the same route at 30 miles per hour. If her total traveling time was 1 hour, what was the total number of miles in the round trip?

  12. Animals break down glucose (C6H12O6) as a source of energy according to the following overall reaction.

    C6H12O6(aq) + 6O2(g) �¨ 6CO2(g) + 6H2O(l) What mass in grams of CO2(g) is produced from the reaction of 15.0 g of glucose?

  13. Consider the reaction.

    4Fe(s) + 3O2(g) �¨ 2Fe2O3(s) If 0.500 mol of Fe reacts with 0.400 mol of O2, what are the limiting reactant and the theoretical yield in moles of Fe2O3 for the reaction, respectively?

  14. mgh=1/2mv^2, solve for the variable v

  15. Three different pairs of numbers that add together to get 1

  16. Which is a stronger base in aqueous solution, IO- or IO3-? Explain.

  17. Consider the following reaction that occurs when natural gas is burned.

    CH4(g) + 2O2(g) �¨ CO2(g) + 2H2O(g) How many moles of water are produced when 6.2 mol of methane are burned? Assume that there is more than enough oxygen present.

  18. The ratio of cups of flour to cups of cooking oil in a cake mix is 3:8 The ratio of cups of cooking oil to cups of water is 6 to 5. There is 3/4 cups of flour required. How many cups of water are required.

  19. 1. A 2.5 kg mass at rest on a horizontal surface is acted upon by an applied horizontal force of 150 N. A frictional force of 100 N acts on the mass. How much work is done on the mass?

    my answer: would the work be 0? 2. When a rock is thrown straight up in

  20. In a baseball a pitcher can accelerate a .15kg ball from rest to 98 mi/h in a distance of 1.7m

    a) what is the average force exerted on a ball during a pitch? b)If the mass of the ball is increased, is the force required of the pitcher increased, decreased

  21. Can someone please check my answers? How are the governments of Jordan and Kuwait different from the governments of the United Arab Emirates and Oman?

    Citizens of Jordan and Kuwait can vote. B. Jordan and Kuwait have monarchs. C. The king of Jordan and emir

  22. A falling stone accelerates at a constant rate of 10ms^2. It is dropped from rest down a deep well and 3s later a splash is heard as it hits the water below.(1) How fast will it be moving as it hits the water? (2)What will be its average speed over the

  23. When x is increased by 5, the result is 60% of increasing x by 15. What is the value of x?

    I got this far: x+5 = 0.60(x+15) x+5 = 0.60x + 9 x = 0.60x + 4 What is the next step?

  24. 1. In moving an object of mass 10 kg through a distance of 8.0 m, 40 J of work is done. The average force exerted is?

    my answer: 320N 2. What is the kinetic energy of a 20 kg object moving at a speed of 10 m/s? my answer: 1000J 3. the gravitational

  25. If the mid-Atlantic Ocean is spreading at 3.0 cm per year, how many years has it taken for it to reach its present width of about 5000 km?

    Express your answer to two significant figures and include the appropriate units.

  26. Two fire wardens are stationed at locations A and B, which are 50 km apart. Each warden sights the forest fire at C. Given that angle CAB is 52 degrees and CBA is 43.0, find the distance from C to the nearer warden, to the nearest 0.1 km

  27. Please check my answers...

    1. Asthma is associated with environmental conditions. True 2. Only one-half of U.S. children with asthma follow their doctor's advice about medication. False 3. The percentage of overweight children has increased only marginally

  28. One pump can empty a pool in 5 days, whereas a second pump can empty the pool in 7 days. How long will it take the two pumps, working together, to empty the pool?

  29. Read the following line from "Not Waving but Drowning."

    "Poor chap, he always loved larking And now he's dead" a. detached b. pleased c. objective d. critical NOT WAVING BUT DROWNING Stevie Smith Nobody heard him, the dead man, But still he lay moaning: I

  30. If y is directly proportional to

    x and y = 65 when x = 33, find y if x = 44 . (Round off your answer to the nearest hundredth.)

  31. Al and Fe react with HCl to produce a chloride salt and hydrogen gas. A .1924g sample of a mixture of Al and Fe is treated with excess HCl solution. A volume of 159mL h2 gas is collected over water at 19C and 841 torr. What is the mass percent by mass of

  32. LOGIC and ARGUMENTS – the simple elements

    Arguments are Composed of THREE PARTS: 1) Premises = basic, commonly accepted reasons – the “why’s,” and “how’s.” 2) Inferences = reasoned “guesses” or based assertions connecting conclusion to

  33. How many milliliters of 0.635M K2CrO4 are needed to precipitate all the silver in 410mL of 0.158M AgNO3 as AgCrO4 ?

  34. 2NaN3(s)==>2Na(s) + 3N2(g)

    How many liters of N2 are produced at STP if the air bag contains 114g of NaN3 ?

  35. A pineapple drink contains 15% pineapple juice. How much pure pineapple juice should be added to 8 quarts of the drink to obtain a mixture containing 50% pineapple juice.

  36. Which are structures in eukaryotic cells?

    Select all that apply. mitochondria DNA nucleus plasmid

  37. Consider an airplane with a total wing surface of 100 square meters (m2). At a certain speed the difference in the air pressure below and above the wings is 5% of atmospheric pressure. What is the lift force on the airplane in units of kN (kilo Newtons)?

  38. (Who, To Whom) is she talking?

  39. Doestrogen anyone know the answers to the unit 8 lesson 4 quiz? Please help asap! Social studies

  40. Laura wants the average amount of money she spends in four days to be no more than $64. On the first three days she spends $71, $62 and $59. What is the greatest amount she can spend on day 4?

  41. 10. David has a small business and is working on an Excel worksheet to help manage his inventory. David

    realizes cell E14 has the wrong output. To check the problem, David should first select cell E14 and look at the _______ to check the formula. A. range

  42. A 2.0 kg box rests on a plank that is inclined at an angle of 65° above the horizontal. The upper end of the box is attached to a spring with a force constant of 17 N/m, as shown in the figure. If the coefficient of static friction between the box and the

  43. Ms. Sue Can You Help Me Answer This Question?

    During the early 1800s, the United States tried to make peace with other countries in order to grow and develop. Give an example of one of these peace efforts and briefly explain what it hoped to accomplish.

  44. A .7178 g sample of a hydrocarbon occupies a volume of 390.7 mL at 65C and 99.2kpa. When the sample is burned in excess oxygen, 2.4267 g CO2 and .4967g H2O are obtained. What is the molecular formula of the hydrocarbon? Write a plausible structural formula

  45. 1. Which of the following best shows the transfer of heat by radiation?

    my answer: c 2. Which of the following best shows the transfer of heat by convection? my answer: b 3. Water has specific heat of 4200 J per kilogram per degree celsius. This means that

  46. Many dairy cows now receive injections of BST, a hormone intended to spur greater milk production. A group of 53 Jersey cows increased average milk production from 43 to 52 pounds per day, with a standard deviation of 4.8 lbs.

    Is this evidence that the

  47. This is a 71-year-old female admitted with a complaint of right-sided weakness. She denies any fever, shortness of breath, cough, headaches, or chest pain. Patient has NIDDM, controlled by diet. Patient currently smokes. Mild right-sided paralysis was

  48. In proton-beam therapy, a high-energy beam of protons is fired at a tumor. The protons come to rest in the tumor, depositing their kinetic energy and breaking apart the tumor’s DNA, thus killing its cells. For one patient, it is desired that 0.10 J of

  49. For the following equilibrium system, which of the following changes will form more CaCO3?

    CO2(g) + Ca(OH)2(s) <--> CaCO3(s) + H2O(l) deltaH(rxn) = -113 kJ My choices are: a) Decrease temperature at a constant pressure (no phase change) B) Increase volume

  50. Sec^2 2u-1/Sec^2 2u = Sin^2 2u

  51. i'm having trouble calculating this. can someone help please?

    A $7,000, 4%, 120-day note, dated March 20, is discounted on July 15. Assuming a 3% discount rate, the bank discount is: a) $1.74 b) $1.77 c) $7.11 d) $17.68 e) None of these .

  52. Kim Davis has decided to purchase a cellular phone, but she is unsure about which rate plan to select. The "regular" plan charges a fixed fee of $55 per month for 1,000 minutes of airtime plus $0.33 per minute for any time over 1,000 minutes. The

  53. Math word problem: There are 25 students in Mrs. Roberts 3rd grade class. There are 9 more boys than girls in the class. How many boys and girls are in Mrs. Robert's class.

  54. Hydrogen is generated by passing hot steam over iron, which oxidizes to form Fe3O4, in the following equation:

    a. if 625 g of Fe3O4 is produced in the reaction, how many moles of hydrogen are produced at the same time? b. how many moles of iron would be

  55. If there are 12 candidates in a city election. The winner will be the mayor and the runner up will be the vice mayor. How many different combinations of mayor and vice-mayor are possible?

    Would it be 12P2 = 132 ? o:

  56. How do you rename a fraction? Like

    2/9 in eighteenths

  57. Write the acid-dissociation reaction of nitrous acid (HNO2) and its acidity constant expression.

  58. Last Saturday Michaela rented 4 movies from the video store. This Saturday she rented 2 movies. Let x represent the cost of renting each movie. Write and simplify an expression for how much more Michaela spent last week renting movies.

    Please help me work

  59. Could you please explain this problem step by step, thank you!

    You are planning to make an open rectangular box that will hold a volume of 50 cubed feet. What are the dimensions of the box with minimum surface area?

  60. A 0.165-kg ball, moving in the positive direction at 10 m/s, is acted on by the impulse shown in the graph below. What is the ball's speed at 4.0 s?

  61. What is the probability that a student in a college of 650 students in both a math major and a computer science major ( assuming these events are independent) If there are 72 math majors and 105 computer science majors?

  62. if x=4 tan theta, express cos(2 theta) as a function of x

  63. (x-8)(x-k) = x^2-5kx+m

    In the equation above, k and m are constants. If the equation is true for all values of x, what is the value of m?

  64. Consider the combustion of liquid methanol,

    CH3OH (l) CH3OH (l) +3/2O2 (g) = CO2 (g) + 2H2O(l) H = -726.5 kJ What is for the reaction represented by this equation? Express your answer using four significant figures

  65. A chemist wants to make 5.5 L of a 0.250 M CaCl2 solution, what mass of CaCl2 (in g) should the chemist use?

  66. A chemist wants to make 4.5 L of a 0.310 M CaCl2 solution what mass of CaCl2 (in g) should the chemist use

  67. 3.57×10−2 mol Ba Express your answer using three significant figures

  68. A sample of gas occupies 3.00 L at 760 torr. Calculate the volume it will occupy at 1.45 atm and the same temperature?

  69. A balloon filled with helium has a volume of 1.oo x 10^3 L at 20 degrees c. What will be the balloons volume at 30 degrees c, if the pressure surrounding the balloon remains constant?

  70. -4x (little 2) =0

    Not sure what name the technique means. I know this is a Quadratic Equation.

  71. A customer wants to mail a package.

    The postal clerk determines the cost of the package to be $18.95, but only 6¢ and 9¢ stamps are available. Can the available stamps be used for the exact amount of postage for the package? Why or why not?

  72. the general "hang time" of a punt is measured to be 4.5sec. if the ball was kicked @ an angle of 63deg. above the horizontal & was caught @ the same level from which it was kicked, what was its initial speed?

  73. Which particles can wind move most easily? Sand, silt, pebbles, or gravel? I put sand but my teacher marked it wrong. Would it be silt? Pebbles and gravel are pretty heavy.

  74. is it difficult to accurately measure prejudice?

  75. Why did democracy work in Athens but not in the United States?

  76. A block of wood of density 0.6g/cm, weighing 3.0N in air, floats freely in a liquid of density 0.8g/cm. Calculate the volume of the portion immersed (g=10ms)

  77. the shape is enlarged by a factor of 2 is the image congruent to the original image

  78. A circle is inside a square.

    The radius of the circle is decreasing at a rate of 4 meters per day and the sides of the square are increasing at a rate of 2 meters per day. When the radius is 3 meters, and the sides are 19 meters, then how fast is the AREA

  79. An inverted pyramid is being filled with water at a constant rate of 25 cubic centimeters per second. The pyramid, at the top, has the shape of a square with sides of length 6 cm, and the height is 9 cm.

    Find the rate at which the water level is rising when

  80. Julia is in the cereal aisle at the grocery store and is looking at the cereal options. The probability that the cereal is in a bag is 0.8. The probability that the cereal has a prize inside is 0.3. The probability that the cereal is in a bag and has a

  81. Show that ∑ ((log 𝑛)^𝑞/𝑛^𝑝)

    converges for −∞ < 𝑞 < ∞ and 𝑝 > 1.

  82. Show that ∑ ((log 𝑛)

    𝑞 /𝑛 𝑝 ) ∞ 𝑛=2 converges for −∞ < 𝑞 < ∞ and 𝑝 > 1.

  83. Urea (CH4N2O) is a common fertilizer that is synthesized by the reaction of ammonia (NH3) with carbon dioxide. NH3 + CO2 = CH4N2O + H2O. In an industrial synthesis of urea, a chemist combines an excess of ammonia with 11.4 grams of carbon dioxide. Balance

  84. O is a dibasic acid H2X .G is a solution containing 1.00g of NaOH in 250cm³ solution.

    1) calculate the concentration of G in mol/dm³ 2) calculate the concentration of O in mol /dm³ 3) molar mass of acid given that 100cm³ of O contains 0.485g of the acid

  85. O is a dibasic acid H2X .G is a solution containing 1.00g of NaOH in 250cm³ solution.

    1) calculate the concentration of G in mol/dm³ 2) calculate the concentration of O in mol /dm³ 3) molar mass of acid given that 100cm³ of O contains 0.485g of the acid

  86. Hydrogen gas reactions with nitrogen to form ammonia according to the following chemical equation:

    H2(g) + N2(g) --> NH3(g) How many grams of H2 are needed to produce 12.15 grams of NH3? (express your answer as numeric only with 3 significant digits)

  87. The Parkside basketball team scored 54 points out of two-point and three-point shots (ignoring free throws for this problem). Parkside scored 25 baskets of these two types. Ms. Pisano reasons that Parkside must have scored 6 three’s and 19 two’s. Is

  88. The marginal profit for selling x souvenir hats is modeled by P'(x)=5-0.02x dollars. If fixed cost is 250 dollars, how do you find the number of hats you would like to sell to maximize profit? Then how do you find the profit for selling that many units?

  89. On one production line in a small custom chip factory, marginal costs decrease rapidly as more chips are made. The marginal cost of making x thousand chips in a day is thought to be C'(x)=40 / the square root of x in hundreds of dollars. Given that it

  90. The marginal profit for selling x souvenir hats is modeled by P'(x)=5-.02x dollars. If fixed cost is 250 dollars, how do you find the number of hats you would like to sell to maximize profit?

  91. On one production line in a small custom chip factory, marginal costs decrease rapidly as more chips are made. The marginal cost of making x thousand chips in a day is thought to be C'(x)=40 / the square root of x in hundreds of dollars. Given that it

  92. Which form of mechanical weathering can produce the most significant and rapid changes on the earth’s surface

  93. A golfer hits a shot to a green that is elevated 3.20 m above the point where the ball is struck. The ball leaves the club at a speed of 19.0 m/s at an angle of 52.0˚ above the horizontal. It rises to its maximum height and then falls down to the green.

  94. 2FePO4+3Na2SO4--->Fe2 (SO4)3+2Na3PO4

  95. What are welfare payments of consumer subsidies?

  96. 1/4 multiply 2540/1

  97. How many kilo calories (kcal) are required to change 1 kg of 0°C ice to 0°C water?

  98. How many Joules of heat are required to raise the temperature of 0.6 kg of water by 28 °C?

  99. A student performs the reaction below in three experiments studying initial concentrations and initial rates. The data is summarised in the table below. Show all your work.

    2 NO(g) + Br2(g) → 2 NOBr(g) a. What is the order of this reaction with respect to

  100. According to scientists the point at which substance boils, melts and freezes are properties of those substances. True or False?


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