题目

如图，某小区规划在一个长30m、宽20m的长方形ABCD上修建三条同样宽的通道，使其中两条与AB平行，另一条与AD平行，其余部分种花草.要使每一块花草的面积都为78m2 ， 那么通道的宽应设计成多少m？设通道的宽为xm，由题意列得方程. 答案：【1】（30-2x）（20-x）=78×6 阅读理解 　　Once there was something wrong with a machine in a factory．The workers could do nothing but turn to a German engineer for help, who drew a line on it and then said,“Take off the part where the line is and change it for a new one．”The machine, with a new line on began running well again．The engineer then asked for ＄30,000 for what he had done．The following were what he wrote on a bill,“The new part only costs one dollar, and knowing where the problem with the machine costs 29,999．” 　　One dollar for changing a new part sounds reasonable but 29,999 dollars is the value of wisdom and knowledge． (1) The factory turned to the German engineer because ________． [　　] A． he had nothing to do in the factory B． there were no other people in the factory C． the workers could not repair the machine D． the workers asked for too much money for repairing the machine (2) The problem of the machine ________． [　　] A． was caused by the German engineer B． was found and solved by the workers C． took the engineer a long time to find D． was just a line (3) According to the engineer, the finding of the problem cost ________． [　　] A． only one dollar B． 29,999 C． nothing D． 30,000 (4) The writer wants to tell us that ________． [　　] A． the engineer asked for too much money B． the workers should pay the money C． the knowledge is worth money D． the new part could cost more (5) The best title for the passage should be ________． [　　] A． The Value of Knowledge B． Helpless Workers C． The Expensive Machine D． The Lucky Factory