题干

小芳在学过自由落体运动规律后,对自家房上下落的雨滴产生了兴趣,她坐在窗前发现从屋檐每隔相等时间滴下一滴水,当第5滴正欲滴下时,第1滴刚好落到地面,而第3滴与第2滴分别位于高1m的窗子的上、下沿,小芳同学在自己的作业本上画出了如图所示的雨滴下落同自家房子尺寸的关系图,其中2点和3点之间的小矩形表示小芳正对的窗子,则:

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    My friend,Victor,is a zoo keeper in the National Zoo.His work is very interesting but it is hard.Sometimes it is dangerous,too.Every morning,the zoo keepers have to get up at five to prepare the food for the animals.Each kind of animal eats special food.For example,the lions must be given meat; the deer must be given grass and leaves; and the parrots must be given fruit and nuts.Sometimes some animals won't let the others eat their food.If this happens,each of them must be fed separately(分离的).
    Every morning each cage (笼子) must be washed by the zoo keepers.This can be dangerous,especially with lions and tigers.To make the work easier,the animals are locked in the sleeping compartments( 隔间) while the cages are being washed.When the animals are sick,the zoo keepers must look after them.Each sick animal is kept in a separate cage and given medicine.Sometimes they must be given injection.It is not easy to inject a sick lion!
    All the keepers live near the zoo.Each of them has a small house.There he lives with his family.They do not have holidays on Sundays and special holidays.Instead,each of them has a day off during the week.Each keeperhas a holiday on a different day from that of the other keepers.
    The most important job of the keepers is to look after the safety of the visitors.People must be stopped from doing dangerous things.Many people have been hurt because they did careless things,like putting their hands into the lion's cage.