--- Oh, my god. I ______ 2 kg. this month.

--- Don't worry. It's normal for a growing teenage girl.

如图，在多面体ABCDEF中，底面ABCD是以AD，BC为腰的等腰梯形，且DC=$\frac{1}{2}$AB,$\angle DAB=60°$，EF∥AC，EF=$\frac{1}{2}$AC，M为AB的中点．

（I）求证：FM∥平面BCE；

（Ⅱ）若EC⊥平面ABCD，求证：BC⊥AF．

阅读下面短文，按要求完成各小题。

     Nick and his friends were talking about things that can bring them luck. “I have a lucky red pen,” said Andy. “I have a lucky coin,” said Peter. “Every time I take a test, I carry my lucky coin.” Nick thought for a moment, and said, “My blue socks.” “Blue socks?” the boys were surprised and asked together. Nick said that every time he wore his blue socks to school before a test, he got a good mark.

    The next day Nick had a Chinese test. He was sad because he couldn't find his blue socks. “Mom!” shouted Nick. “Where are my blue socks? I have a Chinese test today, and I need to wear them.”

  “Don't be silly,” Nick's mom said.“They need to be washed.” “When I wear them, I get a good grade.” Nick said.

  “Did you prepare for your test?” asked Mom.

  “Yes.”

  “Then don't worry about it. Just do your best.” Mom encouraged.

    A few days later, Nick's teacher told him that he got 95 in his test. Nick was so excited that he couldn't wait to tell Mom he did well in his test. Mom said, “It wasn't the blue sock s that made you success. In fact, it was made by yourself.”