Suppose that a random variable y has density function f(y) = ky3e−y/2 if y ≥0 and 0 otherwise. Find k which makes f(y) a density function. Then, find e(y ) and var y.

Adolphin is swimming with her friend. the dolphin jumps to a height of 4.54.54, point, 5 meters above the surface of the water as her friend swims 9.89.89, point, 8 meters directly below her. what is the position of the dolphin's friend relative to the surface of the water? meters

Kaitlin is on s long car trip.every time she stops to buy gas,she loses 15 minutes of travel time.if she has to stop 5 times,how late will she be getting to her destination?

Bonnie borrowed $2400.00 from the bank. each year the bank charges 6% simple interest. how much interest will be owed in one year if no payments are made?