Answer
(a) $\frac{3}{2}$, $10\pi$, $\frac{1}{10\pi}$. (b) see graph.
Work Step by Step
(a) Given $y=-\frac{3}{2}sin(0.2t+1.4)$, compare with the standard form of $y=a\cdot sin(kx+b)$,
we can find the amplitude as $|a|=\frac{3}{2}$, period as $\frac{2\pi}{k}=\frac{2\pi}{0.2}=10\pi$, and frequency of the motion as the reciprocal of the period $\frac{1}{10\pi}$.
(b) see graph.