Any offer can be withdrawn, but not every offer can be revoked.
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An offer is accepted only if there is no alteration.
A. 对
B. 错
A counteroffer terminates the offer and is a new offer.
A. 对
B. 错
A late acceptance must be invalid and have no binding on the offeror.
A. 对
B. 错
An acceptance can be revoked after it becomes effective.
A. 对
B. 错
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