If Earl, a nonmerchant, offered to sell a chair to Isaac, a nonmerchant. Earl's house caught fire and destroyed the chair before Isaac accepted Earl's offer to buy the chair. Consequently,
a) The destruction of the chair constitutes an automatic valid revocation of the offer.
b) The fire does not automatically revoke the offer, but because neither Earl nor Isaac is a merchant, the offer is revocable at any time at Earl's option.
c) Earl did not validly communicate a revocation to Isaac, so Isaac still has the option of accepting Earl's offer; if Isaac accepts the offer, Earl must obtain a similar chair for Isaac or pay Isaac the equivalent value of the chair.
d) Earl's offer is automatically revoked by the fire, unless the offer was a firm offer.