HELLPPP!!
Katrina is asked to simplify the expression -3a-4b-2(5a-7b).
She writes -3a-4b-2(5a-7b) = -3-4b-10a+14b
Which property allows her to do this?
a. the associative property
b. the commutative property
c. the distributive property
d. the additive identity property

Assume that the weights of quarters are normally distributed with a mean of 5.67 g and a standard deviation 0.070 g. a vending machine will only accept coins weighing between 5.48 g and 5.82 g. what percentage of legal quarters will be rejected? round your answer to two decimal places.

School has 204 sixth grade students. if the sixth grade is 30% of the total school, how many students are in the middle school?

Ten times the square of a non-zero number is eqaul to ninety times the number