Kirk has one hour to spend at the gym where he will jog, play handball and cycle. Jogging uses 12 calories per minute, handball uses 10 calories per minute and cycling uses 7 calories per minute. Kirk jogs as long as he cycles. How long should Kirk participate in each of these activities in order to use 590 calories? Find the minutes for cycling.
a. 40 minutes
b. 10 minutes
c. 30 minutes
d. 20 minutes
e. none of these