Excused from recycling(回收利用) because you

Excused from recycling(回收利用) because you live in a high rise with a rubbish chute (垃圾道)? You won't be for long. Miami's Mark Shantzis has made it simple for those living in tall buildings to use the chute and recycle too .
　　In Shantzis' Hi-Rise Recycling System, a chute leads to a pie-shaped container with six boxes that can turn around when operated. The system , which fits in the same space as the chute and container now in use, enables glass , plastic , paper , metal , and other rubbish to go into separate boxes .
　　The system is controlled from a board next to the chute door. The board has a button for each class of recycling materials (as well as for unrecyclables). At the press of a button, a microcomputer locks all other floors' chute door and sets the recycling container turning until the right box comes under the chute. The computer also counts the loads and gives a signal by phone when the box is full. And a particular piece of equipment breaks up the nonrecyclables
　　Sorting(分类) recyclables before they are collected saves the use of expensive materials recovery equipment which otherwise has to do the sorting . Such equipment often makes recycled materials very expensive, so expensive that tons of recyclables remain wasted . Shantzis believes his system could help recycled materials become more cost-effective.
小题1:The purpose in writing this text is _________.

A．to encourage people to recycle their rubbish

B．to introduce a recycling system for high rises

C．to describe the use of computer technology in recycling

D．to explain the need for rubbish collection in high rises

小题2: When he says "You won't be for long" the writer means that _______.

A．you'll soon be living in a cleaner building

B．rubbish chutes will become out of date before long

C．you won't wait long for your turn to recycle rubbish

D．it won't be long before you'll have to recycle your rubbish

小题3: Before dropping rubbish into the chute you have to ___________

A．lock the other floors' chute doors	B．check if the container is full
C．press the correct button	D．break up the rubbish

小题4:The biggest advantage of this new system is that _________

A．it reduces the cost of recycling	B．it saves time and space
C．it saves money for people living in high rises
D．it makes better use of the existing recovery equipment