math
posted by someone .
Surfact of A lake is 31 feet above the surface of B lake. B lake is half as deep as A Lake and the bottum of the B lake is 8 feet below the bottom of A Lake. how deep is each lake?

to determine the number of trout in the lake, a conservationist catches 50 trout, tags them,and throws them back into the lake. Later, 32 trout are caught, and it is found that 5 of them are tagged. Estimate how many trout there are in the lake.