根据百分数的意义,这里是把99粒种子看做单位“1”,
所以发芽率是100%.
故选:C.
258. As soon as the principal ______ the news on the bulletin, the students began gathering in the school garden.
A.mailed
B.sent
C.posted
D.Handed
有机磷酸酯类对神经系统的毒性作用主要损害()
A.神经元
B.轴索
C.髓鞘
D.神经递质
E.以上都