导致放射性突发事件主要原因不包括()。
A.放射性物质丢失、被盗
B.包容放射性物质设备泄漏
C.放射性装置故障或误操作
D.管理不善,造成有毒化学物品散落流式
参考答案:D
句型转换,每空一词。(每小题1分,共5分)
小题1:I like playing table tennis.(就画线部分提问)
you like doing?
小题2:He has a new storybook.(改为一般疑问句)
he a storybook?
小题3:It is time for school now. (改为同义句)
It is time __________ __________ to school now.
小题4:He likes eating candy. ( 改为否定句)
He __________ ________eating candy.
小题5:I play volleyball twice a week. (对划线部分提问)
How__________ __________ a week do you play volleyball?
写出生物种群的指数增长模型及逻辑斯蒂增长模型,并分别介绍其生物学意义?