(a) Does the particle ever move downward?Consider the motion of a particle along a helix given byr(t) = sinti+ costj+ (t^2 - 3t + 2)k, where the k component measures the height in meters above ground and t >= 0.

(b) Does the particle ever stop moving?

(c) At what times does it reach a position 12 meters above the ground?

(d) What is the velocity of the particle when it is 12 meters above the ground?

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