It is really easy to answer. To get to know how much did she spend al together we can simply add up all her expenses and then answer it up.
So if we add the price of the t shirt with that base ball cap we get 8.75 + 1.99 which is equal to 10.74 $. Now adding the magnets price to this it becomes 10.74 + 0.75 = 11.49 $
SO 11.49$ is the total amount of money that she spent on her visit.