请根据以下短文内容,回答短文后面的问题,答题词数不得超过10个单词。
At just 17 years old,Pakistan's Malala is the youngest ever winner of the Nobel Peace Prize.
Malala came to international attention when she spoke up for the rights of all children to have an education. Malala's father was a teacher who ran a school.For her early life,her family lived in the school so she was used to siting in the classrooms before her school age.Now,she can speak three languages and loves learning.
She grew up in Pakistan.The living conditions in her area were very poor and unsafe.Many people were hurt and many schools were closed.Girls especially were not allowed to go to school
Reporters from Britain told the world what was happening with the help of Malala.In 2009,12-year-old Malala wrote 35 diaries on the Internet.She wrote about the difficulties of her life,and about her strong hope for education.Soon after that,Malala's family was chosen to be in a TV program on ordinary children's education because both father and daughter spoke good English,and they cared about children's education.
Malala has now written a book about her life called I Am Malala.The book shows that one person's voice can inspire change in the world.In her speech,she spoke warmly about her aims for education and peace.One sentence she said one day became famous:One child,one teacher,one pen and one book can greatly change the world.
1. How old was Malala when she won the Nobel Peace Prize?