PLEASE HELP A middle school with z students ran a survey to determine the students favorite activities. The table indicates the number of students who enjoy each activity

Giuseppi's pizza had orders for $931.00 of pizzas. the prices were $21 for a large pizza, 514 for a medium pizza, and $7 for a small pizza. the number of large pizzas was two less than four times the number of medium pizzas. thenumber of small pizzas was three more than three times the number of medium pizzas. how many of each size of pizza were ordered?

Which shows the correct substitution of the values a,b and c from the equation 1=-2x+3x^2+1

Solve for n? [tex]z = \frac{3}{4} mn[/tex]