Which line on the graph below has a slope of zero?

On a coordinate plane, line Q is horizontal, line P has a positive slope, line R is vertical, and line S has a negative slope.
P
Q
R
S

Aiden drives to school and back each day. the school is 16 miles from his home. he averages 40 miles per hour on his way to school. if his trip takes 1 hour, at approximately what speed does aiden drive home?

Moira has a canvas that is 8 inches by 10 inches. she wants to paint a line diagonally from the top left corner to the bottom right corner. approximately how long will the diagonal line be?

How many solutions does the nonlinear system of equations graphed below have?