A supersonic plane is flying above at a height H = 4 km directly above a small village. The residents hear the sound t = 10 s after the plane has flown above their heads. How would I find the plane (speed of sound is vs = 330 m/s

Agroup of monkeys is trying to cross the river in a rowboat. the maximum buoyant force on the rowboat is 2,000 n. the weight of the rowboat is 1,000 n. each monkey has a weight of 150 n. how many monkeys can safely cross in the rowboat at one time? explain your reasoning, including any calculations you used to find the answer.