阅读短文，根据短文补全句子，使短文通顺完整、衔接自然。
A: Betty, will we study at school in the future?
B: ____ But we don't use paper, pens or rulers.
A: What will we use?
B: ____
A: But will we use pencils in the art class?
B: ____ We will draw pictures on the computers.
A: ____ How long will we study at school every day?
B: I think we will study for about three hours and then we can play games.
A: Really?
B: ____ It's just my dream.
A: It's my dream too.
，在地球表面附近绕地球沿圆轨道运行的相同质量的人造卫星的动能为
，则
的值最接近下列哪个数值： （ ）