观察如图的图形,它们是按一定规律排列的,依照此规律,第100个图形共有____个五角星.
I haven't heard from my parents .
用显微镜观察玻片标本时,发现视野中央有一个污点,移动玻片或者转动目镜污点均不动,则污点在什么结构上?( )
-- Mum, can I go to the zoo with Jack?
-- When your homework , you can.