已知n对变量值的相关系数r>0,则回归系数()。 A.b>0 B.b C.b=0 D

题型:单项选择题

问题:

已知n对变量值的相关系数r>0,则回归系数()。

A.b>0

B.b<0

C.b=0

D.-1

E.不能确定b>0还是b<0

考点:疾病控制(医学高级)慢性非传染性疾病控制慢性非传染性疾病控制题库
题型:单项选择题

造成婴幼儿退缩性格的原因有()。

A.心理教育

B.驯服式教育

C.识字教育

D.耐心教育

题型:单项选择题

对医学道德行为的道德价值的意志反应是()

A.认知道德评价

B.情感道德评价

C.意志道德评价

D.医学伦理决策

题型:单项选择题

脑脊液主要由脑室内的_________产生,最后经_________主要归入上矢状窦。

题型:单项选择题

On the morning of November 18, 1755, an earthquake shock Boston. John Winthrop, a professor at Harvard College, felt the quake and awoke. “I rose”, Winthrop wrote, “and lighted a candle, looked at my watch, and found it to be 15minutes after four.” John Winthrop hurried downstairs to the grandfather clock. It had stopped three minutes before, at 4:12. Except for stopping the clock, the quake had only thrown a key from the mantel(壁炉台) to the floor.

The clock had stopped because Winthrop had put some long glass tubes he was using for an experiment into the case for safekeeping. The quake had knocked the tubes over and blocked the pendulum(钟摆).Winthrop, therefore, had the key on the floor. The quake had thrown it forward in the direction of the quake’ s motion by a shock coming from the northwest, perhaps in Canada.

小题1:What does “it” in the second paragraph refer to?

A.the floor

B.the key

C.the clock

D.the case小题2:The selection suggests that     .

A.earthquakes are common in Boston

B.John Winthrop was a scientist

C.John Winthrop often had difficulty in sleeping

D.Harvard College was a center for earthquake researching小题3:Professor Winthrop ran downstairs because he wanted to know what had happened to    .

A.the clock

B.his grandfather

C.the key

D.the glass tubes小题4:John Winthrop put some tubes into this clock case because     .

A.he wanted to do an experiment

B.he thought an earthquake was probably to happen soon

C.he thought it safe for them to be put there

D.he wanted to record the exam time of the earthquake

题型:单项选择题

根据法律规定或者当事人的约定,共同责任人不分份额地共同向权利人或者受害人承担的民事责任,称为______。

A.连带责任
B.无过错责任
C.直接责任
D.严格责任

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