1. Four year old Rhys shows considerable aptitude for mountain bike riding. His father engages a 12 year old boy to improve Rhys's biking skills. Rhys's father pays $0 for the first lesson and $30 for each additional lesson. Rhys's father obtains $200 of perceived benefit from commissioning 6 lessons and $250 of perceived benefit from commissioning 7 lessons. Which of the following statements is true:

(a) Rhys's father should commission the seventh lesson because the marginal benefit is greater than the marginal cost.

(b) The marginal benefit of commissioning the seventh lesson is $40.

(c) Rhys's father should not commission the seventh lesson because the marginal benefit is less than the marginal cost.

(d) The marginal cost of the seventh lesson is $50.

(e) Rhys gains no economic benefit from his lessons because he does not pay for them.