Basic Quadratic equation solving help needed!

Marcy is conducting a study regarding the amount of time students at her school spend talking to friends online. which group would give marcy the best results for her study?

Click on the number until you find the right quotient. 12x^a y^b ÷ (-6x^a y)

The cost varies directly with the number of tickets purchased. it costs $145 for 10 people to attend a concert. a. what is the constant of proportionality (k)? b. write the direct variation equation. c. home much does it cost for 8 people? d. graph this situation. be sure to label each axis and give the graph a title.