当m-n=-2时，原式=m2-2mn+n22=(m-n)22=(-2)22=2
— Will there be more trees in the future?
— Yes, _____." [ ]
A. there will be
B. there be
C. there will
河豚毒素含量最高的为河豚鱼的( )。
A．血液 B．肝脏 C．卵巢 D．肾脏
