A girl scout troup has 100 boxes of cookies to sell. Of these 100 boxes 60 are chocolate chip and 40 are sugar cookies. 10 boxes are randomly selected to be sold at a fair.

(a) What is the probability that of the 10 selected boxes 5 are chocolate chip? What distribution are you using and what are the parameters?

x is and Hypergeometric (10,60,100)
I calculated P(X=5)=0.207

(b) If the chocolate chip can be sold for 3 dollars and the sugar cookies for 2 dollars, what is the expected value and standard deviation of the amount of money the girl scouts will make at the fair (assume that all 10 selected boxes will be sold).

My problem is how to calculate this expected value and standar deviation?

I know that the expected value is n M/N for an hypergeometric random variable.
but I can not figure it out how to calculate for all the cases? the book said the value is e(x)=26 dollars and 1.48 for the standar desviation.
Thanks.