Answer
The Amplitude is $ 3$
The Period is $ 2$
See graph below
Work Step by Step
For
$y=a\sin c(x−h) + k$ $y =a \cos c(x−h) + k$,
Amplitude: $|a|$, Period: $\frac{2\pi} {|c|}$,
Given $y = -3 \sin (\pi x)$
The Amplitude is $|-3| = 3$
The Period is $\frac{2\pi}{|\pi|} = 2$
The transformations are as follows
The blue graph represents the graph of $\sin x$
The red graph represents the graph of the given function that is reflected about the x-axis, compressed horizontally by a factor of $ \pi$ and stretched vertically by a factor of $3$
See graph below.