由四舍五入法得到近似数，地球的半径约为6.4×103km，则有（ ）个有效数字，精确到（ ）位。
2；百
A．She is not in the place to judge.
B．The man should blame himself.
C．The business deserves the man’s waiting.
D．She is not good at giving advice.
演化论心理学家认为，人类向来就受到“（）”的训练，以害怕响应威胁是（）。
