题干

下列说法正确的是( )

A:异号两数相乘,取绝对值较大的因数的符号

B:同号两数相乘,符号不变

C:两数相乘,如果积为负数,那么这两个因数异号

D:两数相乘,如果积为正数,那么这两个因数都是正数

上一题 下一题 0.0难度 选择题 更新时间:2018-05-30 05:13:02

答案(点此获取答案解析)

C

同类题1

请认真阅读下面短文,从短文后各题所给的A、B、C、D四个选项中,故答案选出最佳选项。

    The news of Stephen Hawking's death came a great shock to the whole world. To his family, he was “a great scientist and an extraordinary man whose work and legacy(遗赠)will 1 for many years”.

    His parents, both Oxford graduates, placed a high  2 on education and family members were often seen reading books at dinner. 3 known at school as “Einstein”, Hawking was not 4 successful academically. With time, he began to show talents for scientific subjects and decided to read  5 at university. As mathematics was not  6at Oxford then, Hawking chose physics instead.

    Diagnosed with a rare motor neurone disease, Hawking eventually 7 a wheelchair. Though shocked and bitter, Hawking continued his work in physics  8. After the loss of his  9, he communicated through a speech-generating device, which  10 him to produce A Brief History of Time with the help of an assistant.

    Hawking once  11how he felt when first informed of his disease,  12 that he would never realize his potential. “But now, 50 years later, I  13 be more satisfied with my life,” he said.

    Hawking also gained popularity  14 the academic world and appeared in several TV shows. He was featured in the film The Theory of Everything, which  15 his rise to fame and relationship with his first wife, Jane.

    Prof James Hartle, who once worked with him ,praised his unique ability to see through all the clutter(混乱)in physics and get to the  16.” My 17 of him would be…first as a scientist and, second, as a human being whose story is a victory  18 misfortune, which inspired a lot of people.” Prof Jim Al-Khalili pictured Hawking as a  19 person. “He was a fun loving guy. Inside that paralyzed body was someone full of  20 for life,” he said.