The following phhrase is true (T) or false (F)?

1. An agreement cannot occur unless there is an offer and accepptance of that offer.

2. Goods on display in a supermaket are being offered for sale.

3. An acceptance is not valid unless the offeree knows about the offer and has it in mind

4. An offer is rejected if the offeree tries to vary the condition of the offer

5. When instantaneous communication is used, a contract is made as soon as the offer is sent

6. When parties communicate by fax, acceptance cannot occur until the offeror has read the acceptance

7. An offeree who intends to accept an offer can accept through silence

8. A revocation is not valid unless it is received by the offeree

9. Under the postal rule an offer is accepted when an acceptance is posted

10. A revocation by post is valid as soon as the letter is posted.