一个圆柱形容器的底面直径是12厘米,把一块铁块没入水中,水面上升了2厘米.这块铁块的体积是多少立方厘

What did the Dodds do when they went away last summer？

A．They hired someone to stay in their home.

B．They left their pets with neighbors.

C．They rented their house to a student.

D．They asked their gardener to watch their house.

请帮忙给出正确答案和分析，谢谢！

羊性成熟(名词解释)

正常繁殖母羊的生理状态可分为哪几个阶段？

可可脂色价的测定中，显色溶液是()。

A.重铬酸钾水溶液

B.铬酸钾水溶液

C.重铬酸钾硫酸溶液

D.铬酸钾硫酸溶液

请帮忙给出正确答案和分析，谢谢！

Mouthwashes are not effective cure for bad breath mainly because

A．they can"t cover the thick layers of mucus.

B．they can"t get to all the offending bacteria.

C．they can"t mask the bad odor long enough.

D．their strong smell mixes with bad breath and makes it worse.

请帮忙给出正确答案和分析，谢谢！