【判断题】【消耗次数：1】
若某个线性方程组相应的齐次线性方程组只有零解，则该线性方程组可能无解.
①
正确
②
错误
参考答案：
复制
纠错
相关题目
随机题目
【单选题】
Goats are being hired to do the work of people near San Diego. The fires that occurred in Hillborbough four years ago destroyed thirty homes, most of which have been rebuilt. While people were rebuilding the homes, the grasses and bushes were growing back. The area is now so overgrown in bushes that there is again a major danger of fire.The city government put up bids to remove the bushes. The lowest bid they received was $50,000—and that was if the city provided breakfast and lunch for the workers for the six weeks it would take to clear the overgrown area. The city only wanted to give unlimited coffee and a piece of bread a day for each person. When that offer was rejected, the city asked for help on its website.A sheepherder in Montanta and a goat-keeper in San Bernardino read about the city’s plight（困境）while surfing the Web. They both offered to do the job for $25,000. The city government chose the goat-keeper because he lived closer. When he was told that the city dump（垃圾场）was overflowing , the goat-keeper said, “No problem. My goats will eat everything in your dump, except the car engines, of course.” So, for another $5,000, the city killed two birds with one stone. If all goes well, they will invite the goat-keeper and his “family” back every three years. The goat-keeper said that he would probably visit San Diego while his goats were in the dump.According to the passage, __________.
①
the sheepherder offered to do the job for $50,000
②
the lowest bid to remove the bushes was $50,000
③
the sheepherder and the goat-keeper were both addicted to surfing the Internet
④
hiring goats to do the job saved the city government lots of money
【单选题】
He____________ working as if nothing had happened.
①
continue
②
continues
③
continuing
④
continued
【单选题】
The twentieth century is the age of _____________.
①
technic
②
technician
③
technology
④
technological
【单选题】
Some scientists____________ that flowers open at particular times because their internal clocks tell them to do so.
①
receive
②
make
③
believe
④
talk
【单选题】
Client: Hello! May I speak to Mr. Turner?Secretary: ___________
①
I’m sorry. He’s at a meeting now..
②
I am. Speak, please.
③
Hello! Who’re you, please?
④
Hello! Thank you for calling.
【单选题】
Theteacher,aswellasallhisstudents,________bythedancersperformance.
①
wasimpressed
②
wereimpressed
③
impressed
④
hadimpressed