Suppose That the Terminal Point Determined By $\text { t }$

Essay

Suppose that the terminal point determined by $\text { t }$ is the point $\left( \frac { \sqrt { 21 } } { 5 } , - \frac { 2 } { 5 } \right)$ . Find the terminal point determined by each of the following:
(a) $2 \pi - t$ ,
(b) $- t$ ,
(c) $t - \pi$ ,
(d) $4 \pi + t$ .