已知一个多边形的内角度数和是外角度数和的2倍,则它的边数是______.
设这个多边形的边数为n,
(n-2)•180°=2×360°,
解得n=6,
故答案为:六.
Read and choose. (读一读,选择正确答语)
1. — How much is it?
— ______ [ ]
A. It is two yuan.
B. They are ten yuan.
2. — Can I help you?
A. Yes, please.
B. No, it's not.
3. — How much are they?
A. It's eight yuan.
B. They're nine yuan.
4. — What time is it?
A. It's five o'clock.
B. It's rainy.
女性,30岁,放置宫内节育器2年,月经规则,经期7天。近10余天 * * 淋漓出血,伴轻微下腹痛
血HCG为阴性,B超IUD检查正常,最适合的处理是()
A.取环
B.诊刮
C.抗炎止血治疗
D.人工周期
E.肌注黄体酮