6岁儿童正常收缩压应约为（）
A.76mmHg
B.80mmHg
C.84mmHg
D.88mmHg
E.92mmHg
参考答案：E
直线x＋y－1＝0被圆(x＋1)2＋y2＝3截得的弦长等于
You can’t put off ______ your homework．You must do it now．
A．to do
B．do
C．to doing
D．doing
