Answer:
11. Performance of existing duties can never amount to good consideration.
12. Between husband and wife.
13. It has no practical effect on the contract. The whole contract is enforceable.
14. A contract of necessities
15. frustrated mistake
16. The innocent party did or did not believe the statements to be true.
Explanation:
A contract is a binding agreement in which both the parties are liable to fulfill the duties agreed in the contract. There can be terms listed in the contract on which both parties agrees. If there is a vague term, it needs to be cleared while if there is some meaningless term it has no effect on the contract.