如图，在▱ABCD中，点M为CD的中点，且DC=2AD，则AM与BM的夹角的度数为（　　　）

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    What are your favourite fruits? Apples, bananas or oranges? I like apples very much. They are very good for us. I eat two apples every day(每天). My mother likes oranges. My father likes bananas. They are good, too. But I don't like them.