为下列应答语排序。
(____)A.No,it isn't.It's on the first floor.
(____)B.It's cool and cloudy.
(____)C.They're fifty yuan.
(____)D.Yes,they are.
(____)E.It's very pretty.
如图所示,酸甜多汁的水果点亮了一排发光二极管,在这个简单的电路中水果相当于____,如果想控制这个电路的通断,还应在电路中安装____.
平面上有五条直线相交(没有互相平行的),则这五条直线最多有____个交点,最少有____个交点.
下列我国古代科学家中,有哪几位在相同领域内取得了成就?( )
①张衡 ②贾思勰 ③孙思邈 ④沈括 ⑤郭守敬