For each of the following, assume there is consensus. Which of the following are enforceable, according to the rules of consideration?

Question 9 options: answer should be 5

1)	How promised to give his needy friend Jahn $100.
2)	Jones promised in writing to pay an additional $100 to Woody if Woody finished the existing contract on time, according to the terms of the contract.
3)	Baker was so sick of an old chair that, when Venson offered him $10 for it, he agreed promised to sell it to him, although the market value of the chair was $80.
4)	I promise to pay you $1000 because while I was on vacation last month, you decided to shovel my sidewalks and now that I'm home, I really appreciate it.
5)	Marianah promised in writing and under seal to give SAIT a donation of $100.
6)	Petro agreed to pay Ace $250 above the contract price if the company would have his new computer ready ten days earlier than the date specified in the original contract.
7)	Yohan discovered his car battery was dead. He flagged down a passing truck and told the driver he would pay him $125 if the driver would help him out by jump-starting the car. The driver of the truck agreed and started his truck.
8)	Kelvix agreed to sell a farm valued at $190,000 to his nephew for only $50,000.
9)	In a written agreement, you promise to drive your co-worker to Edmonton on Friday.
10)	Sanna moved into an apartment and discovered that a meal kit delivery company that she had never heard of dropped off a meal kit every Friday. Sanna used the kits and really liked the meals. After enjoying 8 meals, the meal kit company tells Sanna that she must pay $40 for each of the 8 meals, for a total of $230.