100 points. 7. you are monitoring birch lake, a small northern minnesota lake that has a healthy walleye population. walleye prefer to feed on crayfish and snails. the lake you are monitoring has a ph of 7.3, so it is a little basic. walleye can handle ph of 6.0 – 9.0. crayfish can handle ph of 6.5 – 8.0. snails can handle a ph of 6.4 – 8.0. the nearby polymet copper mine, if approved, would potentially release acids into surrounding waters, bringing the ph of nearby lakes down to about 6.2 or so. a. what species in this example would not survive in birch lake at a ph of 6.2? b. once those species die out, what will happen to the other species in this situation?