Simplify
Q1) 4a + 7b +5a - b
Q2) 9s - 5s + 2s - s
Q3) 8t + 3r - 7t - 9r

Answer this question! 30 points and brainliest! only if you know the answer.

Tcan be concluded that % of the seniors would prefer to see more candid pictures in this year's edition of the yearbook.

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?