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Required information

When salmon head upstream to spawn, they may encounter a waterfall. If the water is not moving too fast, the salmon can

swim right up through the falling water. Otherwise, the salmon jump out of the water to get to a place in the waterfall

where the water is not falling so fast. When humans build dams that interrupt the usual route followed by the salmon,

artificial fish ladders must be built. They consist of a series of small waterfalls with still pools of water in between them (see

the photo). Suppose the salmon can swim at 8.50 m/s with respect to the water.

If a waterfall is 3.93 m high, how high must the salmon jump to get to water through which it can swim? Assume that they jump straight

up.

m