______是指建在地面上或者建筑物顶部的测量专用标架,作为观测照准目标和提升仪器高度的基础设施。
A.标石 B.三角点 C.砚标 D.天文点
参考答案:C
Read and write.根据答语补全句子。
1. — What is your favourite ?
— Dogs.
2. — What is your favourite ?
— Black.
3. — What is your favourite ?
— P. E.
4. — What is your favourite ?
— Monday.
5. — What is your favourite ?
— Spring.
人类的常染色体有22对,随机选择的两个不同的常染色体性状连锁的机会是()。
A、A
B、B
C、C
D、D