题目

For a year and half, kids sent hurtful messages like “You are ugly.” or “Why are you still alive?” to Rebecca Sedwick. In 2013, Rebecca, then 12, couldn’t stand it anymore. She took her own life near her home in Florida. Soon afterward, Trisha Prabhu read about the story. “I was surprised and heart-broken,” said Trisha, now 15, who is from Naperville, Illinois, “I know that I had to do something to stop this from happening again.” Trisha did some research. Studies show that one fourth to half of all teens in the US have been cyberbullied (网络欺凌). Experts say 6090530是由(　　)个一百万，(　　)个万，5个(　　)，和3个(　　)组成的．