How long was Michael Jordan in the air when he jumped straight up with a speed of 4.5 m/s? I know the answer is 0.918 seconds, but I don't know how to get there.

Acompound machine is also called a machine. a. force b. simple c. complex d. directional

The ph is the a. independent variable b. the dependent variable c. control group

Aparticle's position is given by x = 3.00 - 9.00t + 3t2, in which x is in meters and t is in seconds. (a) what is its velocity at t = 1 s? (b) is it moving in the positive or negative direction of x just then? (c) what is its speed just then? (d) is the speed increasing or decreasing just then? (try answering the next two questions without further calculation.) (e) is there ever an instant when the velocity is zero? if so, give the time t; if not, answer "0". (f) is there a time after t = 3 s when the particle is moving in the negative direction of x? if so, give the time t; if not, answer "0".