I am having a hard time with this one not sure how to set up the problem.

A gas can holds 1.7gal of gasoline. What is this quantity in cubic centimeters?

I know that 1gal=3.785L
I know that 1L=1000cm^3

I have tried 1.7gal*3.785L/1gal=6.4345cm^3.

I just can not figure out what I am doing wrong.

The other two questions that I can not set up for conversions is

8.86*10^11m converted to gigameters

1.57*10^-10m converted to picometers

Your first one is great but you stopped too soon.

1.7 gal x (3.785L/gal) = 6.4345 L (Look at the units. gal cancels and you are left with L. Now you convert to cm^3 by
6.4345 L x (1000 cc/1L) = 6,434.5 cc.
There are two significant figures in the number of 1.7 gal; therefore, you should round the final answer to 2 places. That would be 6,400 cc.

There are 10^9 m in 1 Gm.
There are 10^12 pm in 1 m.

I am still lost on setting up the last 2.

So do I set this up as:

8.86*10^11m (1Gm/10^9m)=8.86*10^11/10^9 since my meters cancel? Which then gives me 8.86^20

Your set up is right. Your math is wrong.

That gives you 8.86 x 10^2 = 886 gigameters. (and you were smart to set up up that way to make the meters cancel and leave gm.) When you divide exponents you subtract; therefore 10^11/10^9 = 10^2.

To convert the quantity of gasoline in gallons to cubic centimeters, you can follow these steps:

Step 1: Start with the given value of gasoline in gallons. You have correctly identified that 1.7 gallons is the quantity in question.

Step 2: Use the conversion factor that relates gallons to liters. You mentioned that 1 gallon is equal to 3.785 liters. So, you can express 1.7 gallons as 1.7 * 3.785 liters.

Step 3: Use another conversion factor that relates liters to cubic centimeters. You correctly stated that 1 liter is equal to 1000 cubic centimeters. Therefore, you can multiply the liters from Step 2 by 1000 to obtain the quantity in cubic centimeters.

Putting these steps together, the calculation would be:

1.7 gallons * 3.785 liters/gallon * 1000 cubic centimeters/liter

Now, if we do the math, we get:

1.7 * 3.785 * 1000 ≈ 6435.05 cubic centimeters

Therefore, the quantity of gasoline in the gas can is approximately 6435 cubic centimeters, not 6.4345 cm^3 as you initially calculated.