beginning physics problem

Please help with this problem. I don't understand how you can know a quantity of rainfall over the given city area just by knowing 1.1 cm.

The problem:
A heavy rainstorm dumps 1.1 cm of rain on a city 5 km wide and 9 km long in a 2-h period.

(a)How many metric tons (1 metric ton = 10^3 kg) of water fell on the city? (1 cm^3 of water has a mass of 1 gram = 10^-3 kg.)

For A, I know that if I can find kg of water, I can find metric tons easily enough. I could find kg by the 1cm=1g=10^-3kg, but I don't know how to find out how much rain was dropped on the city given the dimensions and 1.1 cm. How do you relate these two?

Thanks,

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Recognitions:
Homework Help
 Quote by wadesweatt Please help with this problem. I don't understand how you can know a quantity of rainfall over the given city area just by knowing 1.1 cm. The problem: A heavy rainstorm dumps 1.1 cm of rain on a city 5 km wide and 9 km long in a 2-h period. (a)How many metric tons (1 metric ton = 10^3 kg) of water fell on the city? (1 cm^3 of water has a mass of 1 gram = 10^3 kg.) (b)How many gallons of water was this?
Welcome to PF.

Depth of water times area is volume isn't it?

Looks like you have what you need.
 so does this mean I should multiply 1.1 cm x 45 km? or should I convert 1.1 cm to 1.1x10^-5 km, and then multiply? And then that quantity is my volume of rainfall (in km?)...which I can then relate to cm>grams>kg>metric tons.

beginning physics problem

ok i got it.

Thanks.

Recognitions:
Homework Help
 Quote by wadesweatt ok i got it. Thanks.
Yes you do have it.

Good luck.