Please answer and explaine all and i will thumbs up thanks =)

1a - Griffin agreed to pay his nephew, Eric, $25,000 if he would refrain from drinking alcohol, using tobacco, and playing cards until he finished college. Eric did not drink alcohol, use tobacco or play college throughout college. Griffin, however, refused to pay Eric the $25,000. He argued that the agreement was not supported by consideration by Eric. Did Eric provide any consideration for this to be a valid contract?

1b-Chevy bought 10 sunglasses from Tina for $20.00 each. The next day, Chevy saw Rex selling the same sunglasses for $3.00 each. Chevy got really angry and insisted that Tina refund her $13.00 for each of the 10 sunglasses. Will a court require Tina to refund the money to Chevy?

1c-Shiv says to his son, Kush, in consideration of the fact that you received an A in your business law course, I promise to pay you $1,000. Is this a valid contract?

1d-A fire breaks out in GHALL. The dean immediately calls the fire department and says that GHALL is on fire, and if the fire department comes to put it out, LeBow will donate a brand new fire truck to the fire departmetn. The fire department gets there in 3 minutes, and puts out the firse with little damage to the building. Is there a contract between LeBow and the fire department? Why or why not?