Please help with number 1
tell me if the rest are wrong please
thank you

What is the measure of ac? 5 units 13 units 26 units 39 units 3x- 2b 6x + 9

The number of chocolate chips in a bag of chocolate chip cookies is approximately normally distributed with a mean of 12611261 chips and a standard deviation of 118118 chips. (a) determine the 2626th percentile for the number of chocolate chips in a bag. (b) determine the number of chocolate chips in a bag that make up the middle 9696% of bags. (c) what is the interquartile range of the number of chocolate chips in a bag of chocolate chip cookies?

Ithink i know it but i want to be sure so can you me out ?