Let \(X\) be a discrete random variable with

\(x\)	-1	3	7
\(P(X=x)\)	0.5	0.2	0.3

1. Compute the mgf of \(X\).
2. Compute the mean two ways: using the definition, and using the mgf. Confirm that you get the same answer.
3. Compute the variance two ways: using the definition, and using the mgf. Confirm that you get the same answer.