A. Snails and crayfish would not survive in Birch Lake at a pH of 6.2.
B. Once they die out, the walleye will disappear as well.
Walleye: pH 6.0 — pH 9.0
Crayfish: pH 6.5 — pH 8.0
Snails: pH 6.4 — pH 8.0
At pH = 7.3, all three can survive.
At pH = 6.2, snails and crayfish will die out.
Then, the walleye will disappear because <em>their food supply has vanished</em>.
The amount of heat needed to vaporize the given amount of water is the product of the amount in grams and the latent heat of vaporization in cal per gram. That is,
H = (540 calories / gram)( 500 grams) = 270,000 cal
Thus, the heat needed is 270, 000 calories. The answer is letter C.
Usual s I have no idea sorry
