如图,有一只棱长为20厘米的正方形盒子,一只蚂蚁从A点出发,沿着正方体木箱的外表面爬行到C′D′的中点P的最短路线长为( )
A:1017厘米
B:50厘米
C:1013厘米
D:30厘米
补全表格申所缺信息。
People
Things they did
Time
Places
Jane
Helped kids____
Every Friday
In the club
Sam
Helped to give food to the poor
On Thanksgiving Day
In a local____
Paul
Helped to____
On Clean-up Day
In a local park
Alice
____
At a local animal house
That's the man ________ house was destroyed in the storm.
关于仪器的用途,下列叙述中不正确的是( )