Can someone please help me with these 3 questions? due in 3 days

Erin bought christmas cards for $2 each to send to her family and friends. which variable is the dependent variable?

50 people men and women were asked if they watched at least one sport on tv. 20 of the people surveyed are women, but only 9 of them watch at least one sport on tv. 16 of the men watch at least one sport on tv. make a a two-way table and a relative frequency table to represent the data.

Solve the following pair of equations for x and y: ax/b_ by /a= a +b; ax - by = 2ab