What is the value of the expression -c+(-d) when c=-3.5 and d= -12.8

You were told that the amount of time lapsed between consecutive trades on the new york stock exchange followed a normal distribution with a mean of 15 seconds. you were also told that the probability that the time lapsed between two consecutive trades to fall between 16 to 17 seconds was 13%. the probability that the time lapsed between two consecutive trades would fall below 13 seconds was 7%. what is the probability that the time lapsed between two consecutive trades will be between 14 and 15 seconds?

Can someone answer this question for me

A(1,1) b(-3,0) c(-4,-1) d(3,-2) drag it to correct position