病毒通常只含有一种核酸,由此可知,“SARS”病毒的遗传物质中含有核苷酸的种类及碱基的种类分别是
A:1、4
B:5、8
C:4、4
D:4、5
计算: −273+16−214 .
若两圆的圆心距为3,两圆的半径分别是方程x2-4x+3=0的两个根,则两圆的位置关 系是 ( )
We have classes from Monday to F____ .
My sister enjoys l____ to pop music.
I’m s____ for taking your pen by mistake.
The little boy cried s____ when his best friend moved to another city.
Lily has a good h____ of reading English stories every day.
125厘米=____分米____厘米