上升10米记作+10米,那么下降10米记作-10米。[ ]
正确
Can you ____ your brother from that group of people?[ ]
A. pick up
B. pick out
C. bring up
D. bring out
仪器法测定两次测值绝对误差不大于()时,应取两次测值的算术平均值作为砂浆的含气量。