Say whether each of the following is negotiable or not, and why

1. By Dubious to Shady: "I owe Shady $250 which I will pay him on demand. Signed, Dubious."

2. "October 10, 1995. I promise to pay Dubious Used Cars $6000, thirty days after date. Signed, Betty Baker." 3. October 19, 1995 Pay to the order of Dubious Used Cars, Inc.......$_______ Fifty and 00/100--------------------------------dollars Signed, Alice Ace Enormous Bank 1414 14th St. City, State, Zip 14780978978909 09873987, etc.

4.We promise to pay Big Transmission Co., or order, $800, payment to be made from our account #2. Signed, Dubious Used Cars, Inc, Dubious, Pres."

5.Sally Student to the University for her final tuition payment, a paper including this statement: "to be paid out of my first month's income after graduation."

6. To Dubious from a Mexican national, a note in proper form but payable in Mexican pesos

7. "On or before January 15, 2020, I promise to pay DUC $13,000 in the form of antique auto parts, quantity and quality approved by both parties."