长方体的长、宽、高之比是1：2：3，对角线长是214，则长方体的体积是 ____

Friend is better than fortune. Friend is worse than poison in some cases. The two sentences above are opposite and seem to be unreasonable but they can be explained as follows: the first refers to all good friends who drive us towards good while the second all bad ones who lead us to wrong ways.
My ideal friend is of course a good friend whose goodness is shown below---he has no bad likings, such as smoking and drinking. He lives in frugality (节俭). He studies hard so as not to waste his golden time. At home he honors his parents and loves his brothers; at school he respects his teachers and shares feelings with his classmates. He treats those truly who are true to him. In a word, he has all the good characters better than mine. I can follow him as a model. With his help I am free from all difficulties.
Indeed, if I have such a person as my friend, I shall never fear difficulty and I shall never know the existence of the word "failure".
小题1:This passage tells us (   )

A．how to make friends with others

B．how the writer' s friend helps him

C．what kind of person the writer's friend is

D．what kind of person we should make friends with

小题2:An ideal friend means (   )

A．a true friend

B．a false friend

C．an imaginary friend

D．an excellent friend

小题3:From the passage we can learn that (   )

A．the writer and his ideal friend have a lot to learn from each other

B．the writer has a lot to learn from his ideal friend

C．the writer's ideal friend has a lot to learn from him

D．the writer has only a little to learn from his ideal friend

小题4:From the second paragraph, we can infer the writer is sure that (   )

A．nothing cannot be done with friend
B．only the first sentence is reasonable	C．he who does not smoke or drink must be a good friend
D．good friends should always help each other