Greta loses her two dogs. She puts signs all over town that offer a $50 reward for the return of her dogs. Al and Ben see the posters, and both go find a dog. Al finds one of Greta's dogs, but Ben only finds a look-alike. Charlie does not see the posters, but finds a dog with Greta's address on it. If all three boys show up at Greta's house, who, under the common law of contracts, will Greta have a legal obligation to pay?

Al

Explanation:

In order for a contract to be formed, both parties must reach an agreement (usually through offer and an acceptance of terms). The offer made by Greta was a $50 reward for her missing dogs, Al and Ben agree to the contract by searching for the dogs. Since Al finds and returns one of the Dogs, Greta has an obligation to pay Al. As for Ben, since he failed to meet the terms, he should not be paid. On the other hand, since Charlie never saw the posters, there was no contract formed because he could not possibly agree to terms he was not aware, and Greta has no legal obligation to pay Charlie.

Therefore, Greta has a legal obligation to pay Al.