a salmon fishing boat on bc river traveled upstream in 4h. returning downstream at the speed, it took 3h. the distance was 100km each way. a) find the speed of the fishing boat in still water. b) find the speed of the river's current.

The position of a moving particle is given by the position function: f(t)=-9t-t^2-0.2t^3+0.1t^4 0 a. at what time does the particle reverse direction? b. when is the displacement positive? (round one decimal place and answer in interval notation) c. when is the displacement negative? (round one decimal place and answer in interval notation) d. when is the particle’s acceleration positive? (round one decimal place and answer in interval notation) e. when is the particle’s acceleration negative? (round one decimal place and answer in interval notation)