Choose the word or phrase that correctly completes the sentence. i to bed two hours before it started raining.
a. had goneb. am goingc. had wentd. went

I feel like this is conditional but I'm not too sure, I would go with A because it is a perfect past tense while D is simple past tense (I would use D is normal conversation though) 

D would be like answering a question "what did you do last night?" "I went to bed two hours before it started raining" 

A is like you're telling someone what you have already done using active voice "I had gone to bed two hours before it started raining" 

Take what you will from this, my friend. Sorry I can't be more of a help 

To solve this integral, what you can do is split it up as follows: (1) ∫40(x2−4)dx=∫40(x2)dx−∫40(4)dx. to integrate  4  as an  indefinite integral, a good rule of thumb is  by  an equation below  for  polynomials; . (2) ∫xa=xa+1a+1+c , where a is any number. c denotes some constant that is crucial when doing