Hi! Can someone help me with this math sheet as you can see I have tried to answer some and I got 2 right but I don’t really get it. I would really appreciate your help!

The number of chocolate chips in an 18-ounce bag of chocolate chip cookies is approximately normally distributed with a mean of 1252 chips and standard deviation 129 chips. (a) what is the probability that a randomly selected bag contains between 1100 and 1500 chocolate chips, inclusive? (b) what is the probability that a randomly selected bag contains fewer than 1125 chocolate chips? (c) what proportion of bags contains more than 1225 chocolate chips? (d) what is the percentile rank of a bag that contains 1425 chocolate chips?

Determine the difference: 3.2 × 1010 – 1.1 × 1010. write your answer in scientific notation.

98 point question what is the record for most points in one