If isaac has 21 green marbles and 7 blue marbles and wants to make equal groups with none left over, what is the greatest number of groups he can make?

Me because some of question i don’t understand

What is the measure of angle tvu shown in the diagram below

Solving systems of linear equations: tables represent two linear functions in a systemöwhat is the solution to this system? 0 (10)0 (1.6)0 18,26)0 18-22)