A charitable organization solicits donations by telephone. Employees
are paid $60 plus 20% of the money their calls generate each week. The
amount of money generated in a week can be viewed as a random variable
with mean $700 and standard deviation $130. Find the mean and standard
deviation of an employee’s total pay in a week.

The Mean would just be 60+.2*700 = $200

But what would the standard deviation be? var(x+.2y)? That gives me $26 I think?