They were still _____their friends after their child`s long illness.
They were still _____their friends after their child`s long illness.
The young teacher who has a ____face can make his classes ____and interesting.
在△ABC中，AC＝AB，∠BAC＝α，D为线段AB上的动点，连接DC，将DC绕点D顺时针旋转α得到DE，连接CE，BE．
Behind the dancer there was a woman _______a large diamond ring.
The diamond is _________.
This kind of glasses manufactured by experienced craftsmen ______comfortably.
Betty doesn`t have enough money to buy that coat. It`s very ___. The price is too_____.
It`s bad manners to laugh _____others when they are _____ trouble.
Has your teacher given you any advice______ your study?
某公司计划购进一批原料加工销售，已知该原料的进价为6.2万元/t，加工过程中原料的质量有20%的损耗，加工费m（万元）与原料的质量x（t）之间的关系为m＝50＋0.2x，销售价y（万元/t）与原料的质量x（t）之间的关系如图所示．
（1）求y与x之间的函数关系式；
（2）设销售收入为P（万元），求P与x之间的函数关系式；
（3）原料的质量x为多少吨时，所获销售利润最大，最大销售利润是多少万元？（销售利润＝销售收入﹣总支出）．
