以原点为中心，把点P（1，3）顺时针旋转90°，得到的点P′的坐标为（   ）

设服从二项分布$B\left(n,p\right)$的随机变量$\zeta$的期望与方差分别是15和$\frac{45}{4}$，则n、p的值分别是（   ）．

    It is early in the morning, about seven o'clock. Peter is on the bus. He's going to school. There are many people on the bus and it is a bit hot. Peter is sitting by a window with a book in his hands. The bus driver is driving slowly(慢地). Most people on the bus are using their mobile phones. A girl in a red sweater is standing near Peter. She looks very happy. She is reading some funny things on her mobile phone. A fat boy behind him is busy playing games on  his mobile phone. A tall man is Jack. He is listening to music on the mobile phone. He’s about thirty years old. They are all busy and happy.

家中有亲情，也有矛盾。家可以是乐园，也可以是樊笼。增进家庭温馨要沟通，增进家庭和睦要沟通，增进家庭亲情要沟通。