A company plans to develop a prototype weeding machine that uses cutting blades with optical sensors and microprocessors that distinguish weeds from crop plants by differences in shade of color.The inventor of the machine claims that it will reduce labor costs by virtually eliminating the need for manual weeding.
Which of the following is a consideration in favor of the company’s implementing its plan to develop the prototype?
There is a considerable degree of variation in shade of color between weeds of different species.
The shade of color of some plants tends to change appreciably over the course of their growing season.
When crops are weeded manually, overall size and leaf shape are taken into account in distinguishing crop plants from weeds.
Selection and genetic manipulation allow plants of virtually any species to be economically bred to have a distinctive shade of color without altering their other characteristics.
Farm laborers who are responsible for the manual weeding of crops carry out other agricultural duties at times in the growing season when extensive weeding is not necessary. 请问为啥选D不选E啊？
GWD1-Q13In the United States, of the people who moved from one state to another when they retired, the percentage who retired to Florida has decreased by three percentage points over the past ten years. Since many local businesses in Florida cater to retirees, this decline is likely to have a noticeably negative economic effect on these businesses.
Which of the following, if true, most seriously weakens the argument?
A. Florida attracts more people who move from one state to another when they retire than does any other state. B. The number of people who move out of Florida to accept employment in other states has increased over the past ten years. C. There are far more local businesses in Florida that cater to tourists than there are local businesses that cater to retirees. D. The total number of people who retired and moved to another state for their retirement has increased significantly over the past ten years. E. The number of people who left Florida when they retired to live in another state was greater last year than it was ten years ago.