HELP ASAPPP DUE IN A COUPLE MINUTES. WILL GIVE BRAINIEST! can someone do these 3 questions for me please !!

(PLEASE HELP WITH 7,8,9)

*please don't put none related answers to get points !! *​

Add the two expressions 3.8b - 7 and 2.9b + 9 enter your answer in simplified form

Afunction, f(x), represents the height of a plant x months after being planted. students measure and record the height on a monthly basis. select the appropriate domain for this situation. a. the set of all positive real numbers b. the set of all integers oc. the set of all positive integers od. the set of all real numbers reset next

Point r divides in the ratio 1 : 5. if the coordinates of e and f are (4, 8) and (11, 4), respectively, what are the coordinates of r to two decimal places?