Word problem dont know where to begin

For an upcoming concert, each customer may purchase up to 3 child tickets and 3 adult tickets. let C be the number of child tickets purchased by a single customer. The probability distribution of the number of child tickets purchased by a single customer is given below.

----------------------

C |0 |1 |2 |3 |

P(c) |0.4|0.3|0.2|0.1 |

----------------------

A) Compute the mean and standard deviation of c

b) suppose the mean and the standard deviation for the number of adult tickets purchased by a signle customer are 2 and 1.2, respectively. Assume that the number of child tickets and adult tickets purchased are independent random variables. Compute the mean and the standard deviation of the total number of adult and child tickets purchased by a single customer.

c) Suppose each child ticket costs $15 and each adult ticket costs $25. Compute the mean and the standard deviation of the total amount spent per purchase.

Anyone want to help me on how to just start this problem?I'm sure ill come back with more questions after.