Halcitron wrote:
Since you are too lazy to do your homework here's a bonus question.

What if you have a drainage canal, 15 feet wide and 10 feet deep.
Water is flowing, and the depth is 2 feet on the wall markings. You
look upstream to the mountains and it is raining steady. You have
3-30 inch diameter x 20 foot culverts, side by side, in the culvert
and they are covered in concrete, with a road over them. Height from
stream bottom to road is 5 feet. You have someone 100 feet upstream,
drop a floating object in the water, and it takes 10 seconds to reach
you.

How many gallons per minute are flowing through the culverts?

At what flow rate will the flow of water, exceed the capacity of the
culverts, and flow over the top of the road:
by 1 inch?
by 12 inches?
by 48 inches?


Better:
"How much water flows out of the mouth of the Mississippi per year. Give two
methods:

Answer 1:
Assume width of river at the mouth is two miles, flow is 5MPH and average
depth is five feet. Turn crank.

Answer 2.
Assume Mississippi drains the center half of the country (from Rockies to
Appalachia). That is, 1500 miles E-W, and 1000 miles N-S. Further assume
this area gets 50" of rainfall per year. Turn crank.