Do you like walking? A 13-year-old girl named Jenny likes walking very much. She likes walking because she thinks it is good for her health. “It’s about 6 kilometers from my home to school. I get up at 6:00 every morning. After having breakfast, I walk to school. I can enjoy the beautiful scenery on the way. I feel very happy. I can also think about what to do or how to do things at school on the way,” says Jenny. “My father buys a new car and he wants to take me to school every morning. But I think I need to exercise and I hope my father can exercise, too. Now he often walks to work. After dinner, my father, my mother and I often take a walk in the park near our house. I have a healthy and happy family.”

小题1:How does Jenny get to school every day?

A．By car.

B．On foot.

C．By bus.

D．By bike.小题2:Who does Jenny go walking with?

A．Her mother.

B．Her father.

C．Her parents.

D．Her classmates.小题3:How far is it from Jenny’s home to school?

A．About 3 kilometers.

B．About 6 kilometers.

C．About 7 kilometers.

D．About 8 kilometers小题4:Why does Jenny like walking?

A．It makes her healthy.

B．It’s funny.

C．She can get up late.

D．It makes her happy.小题5:What does the underlined word “scenery” mean?

A．旅程

B．活动

C．风景

D．经历

把一个外观体积为17.8cm³的空心铜球放入水中，恰好处于悬浮状态，求：

（1）空心铜球的重力？

（2）球的空心部分的体积？（ρ_铜=8.9×10³kg/m³）