Help me on #21 please help me please thank you

In each bouquet of flowers, there are 2 roses and 3 white carnations. complete the table to find how many roses and carnations there are in 2 bouquets of flowers.

Which ordered pair (c,d) is a solution to the given system of linear equations- c+2d=13 -9c-4d=-15

Tom wants to order tickets online so that he and three of his friends can go to a water park the cost of the tickets is 16.00 per person there is also a 2.50 one-time service fee for ordering tickets online write an expression in term of n that represents the cost for n ordering tickets online