Answer
See the picture below.
Work Step by Step
The parent function is $2^x$ (with red) the given function is $2^{-x}$ (with blue).
For every corresponding x-value the following equation is true:
$f(-x)=g(x)$ this means that the graph is reflected across the y-axis.
Here is the table of values of the given function:
$f(-2)=2^{-(-2)}=2^{2}=4$
$f(-1)=2^{-(-1)}=2^1=2$
$f(0)=2^{0}=1$
$f(1)=2^{-1}=\frac{1}{2}$