Find parametric equations for the path of a particle that moves along the circle
x2 + (y − 1)2 = 16
in the manner described. (Enter your answer as a comma-separated list of equations. Let x and y be in terms of t.)
(a) Once around clockwise, starting at (4, 1).
0 ≤ t ≤ 2.
(b) Four times around counterclockwise, starting at (4, 1).
0 ≤ t ≤ 8.
(c) Halfway around counterclockwise, starting at (0, 5).
0 ≤ t ≤ .