Janice has final exams in Algebra 1 in biology and Fridays she has less than 12 hours to study for the exams and her mom says she must spend more time on algebra and biology which of the following constraints can be used to represent the situation?​

Quick translate "x is 12 units from 20" into an equation. what are the values of x being described? if you can answer any of my other questions that'd be great too

Mrs. morton has a special reward system for her class. when all her students behave well, she rewards them by putting 3 marbles into a marble jar. when the jar has 100 or more marbles, the students have a party. right now, the the jar has 24 marbles. how could mrs. morton reward the class in order for the students to have a party?

∆red ≅ ∆ by rule will give brainiest if possible