. A BMX race track charges a one-time membership fee and an entry fee per race. One racer paid a total of $76 after 3 races. Another racer paid a total of $124 after 7 races. a) Which variable is the...

.  A BMX race track charges a one-time membership fee and an entry fee per race.  One racer paid a total of $76 after 3 races.  Another racer paid a total of $124 after 7 races.

1. a) Which variable is the independent variable? Which variable is the dependent variable?  Explain why in at least one complete sentence.

1. b) What is the entry fee per race?