You are considering which of two summer jobs to take. Laidback Larry's have less demand for your time but pays more. You will work 100 hours in June, 110 hours in July and 140 hours in August.

They pay you $25 an hour. Alternatively, you can go work for a Demanding Dave's where you will work 180 hours in June, July and August each for $20 an hour.

You always have the ability to pickup local work for $12 an hour and thus value your own time $12 an hour. You can save at a rate of .25% a month:

a. How much better is the Laidback Larry's than your default option of working for $12 an hour? 

b. How much better is Demanding Dave's than your default option of working for $12 an hour? 

c. Which job would you take?