A trampolinist flies straight up into the air, then back down onto the trampoline, where she comes instantaneously to rest when the trampoline is fully stretched. Rank in order, from largest to smallest, her apparent weight. a. When she is instantaneously at rest.

b. Just before she leaves the trampoline.

c. When she is at the top of her flight.

(Wapp)c, (Wapp)b, (Wapp)c

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".