If x + y = 13 and y = 2, then which of the following is true according to the substitution property? I'm pretty sure it's x = 13 - y but I want to be sure

An empty bucket is placed under a faucet dripping at a constant rate of 4 milliliters per minute. with the given information, which of these statements is a reasonable conclusion? a there will be 24 milliliters of water in the bucket after 16 hour. b there will be 60 milliliters of water in the bucket after 14 hour. c there will be 160 milliliters of water in the bucket after 20 minutes. d there will be 100 milliliters of water in the bucket after 40 minutes.

Yo need asap pls ! markin da brainiest too !

Whats are the trickiest steps to do when adding or subtracting rational expressions? how does knowledge of rational numbers u in adding and subtracting rational expressions?