压缩试验(眼科检查)
参考答案:
压缩试验(眼科检查):发现球后占位性病变时,用探头置于眼睑上轻轻向眼球加压,使压力传递到病变区,如果病变变形,则多为囊性占位或海绵状血管瘤。
如图所示,匀强电场方向平行于xOy平面,在xOy平面内有一个半径为R=5 cm的圆,圆上有一动点P,半径OP与x轴方向的夹角为θ,P点沿圆周移动时,O、P两点的电势差满足UOP=25sinθ(V),则该匀强电场的大小和方向分别为 ( )
A.5 V/m,沿x轴正方向
B.25 V/m,沿y轴负方向
C.250V/m,沿x轴负方向
D.500 V/m,沿y轴正方向
根据情景,选择正确的英文表达。
1.你想邀请别人一起去溜冰,可以说: [ ]
A. Do you like skating?
B. Let's go skating.
C. Sounds good.
2.你想问别人会不会拉小提琴,可以说: [ ]
A. Do you play the violin?
B. This is your violin, I think.
C. Can I have a look?
3.听到爸爸提议去吃热狗,你商兴地说: [ ]
A. No, I'd like a hot dog.
B. Great!
C. Here you are.
4.你想知道订书机用英语怎么说,可以问: [ ]
A. What's this in English?
B. Is this a stapler?
C. It's a stapler.
5.你不知道他的铅笔在哪里,你问: [ ]
A. What's in his pencil?
B. Where's her pencil?
C. Where's his pencil?