AMC 8 1989 Problem 19

The graph below shows the total accumulated dollars (in millions) spent by the Surf City government during $1988$. For example, about $.5$ million had been spent by the beginning of February and approximately $2$ million by the end of April. Approximately how many millions of dollars were spent during the summer months of June, July, and August?

$\text{(A)}\ 1.5 \text{(B)}\ 2.5 \text{(C)}\ 3.5 \text{(D)}\ 4.5 \text{(E)}\ 5.5$