Michael Jackson was one of the world's best singers. He was born in the middle west of the city of Gary， Indiana， in 1958. He began singing with his four brothers. They called the group， “The Jackson Five”. The group became very popular after appearing on a television program. In 1970 the group made their  first record with the name of I Want You Back. It was very popular. One of their hit records was Never Say Goodbye.

    Michael was good at dancing as well as singing， for example， his dance moves and moon walking. He was asked to act in a film in 1978 for the first time， and in the same year he made a record on his own， which was sold eight million copies all over the world.

    Michael nearly didn't go out because he was too famous. Once his fans went off in a faint(晕倒）when they saw him at the concert. No one can do it by now. He lived in a large house and kept lots of animals. He never ate meat. He often raised money for charity. This made him win the Guinness world Records（吉尼斯世界纪录）in 2006. He died on June 25th， 2009， but he would live in our hearts forever.

一种细胞，每隔1小时死亡2个，剩下的每个活细胞分裂为2个新细胞．如果最初有7个活细胞，问10小时后有____ 个活细胞．

我来猜。

直追前人。

             谜底是____。