Answer
See the image below.
Work Step by Step
(a) $y=f(2x)$, in this case we have to shrink the graph of $f$ horizontally by a factor of 2.
(b) $y=f(\frac{1}{2}x)$, stretch the graph of $f$ horizontally by a factor of 2.
(c) $y=f(-x)$, reflect the graph of $f$ about the $y$-axis.
(d) $y=-f(-x)$, reflect the graph of $f$ about both the $y$-axis and $x$-axis (in this case it doesn't matter which reflection will be done first; in both cases we will get the same graph).
