Learn English – Do I say “where is it there” or “where it is there” to ask where a place is located

Whether is not a question word, although it looks like one.

Question words beginning with wh are the following:

• what
• which
• where
• who
• whose
• when
• why

The rule for making questions using question words is fairly simple:

Question word + auxiliary + subject + infinite or, "QUASI" is a useful acronym. ^{(It is not infallible but it works most of the time)}

1) Which colour did she choose to make it? Blue or green? (if there is a limited choice)

2) What colours did she use? (a wider choice of colours is inferred here)

3) Who made it? Did you? OR "Was it me or you?" (in this case, who is the subject of the question and does not require an auxiliary)

You can omit the wh question word and ask a yes/no type question.

Auxiliary + subject + infinite

• "Did you use blue or green?" asked Maria.
• Maria asked, "Did you make it?"

If you wanted to use whether you have to rephrase your sentence. Note that the following are not questions. There is no question mark at the end.

• Maria asked whether she used blue or green.
• Maria asked whether [name] made it or not.

If you really need to make questions with whether then the following is acceptable

• Do you know whether she used blue or green to make her scarf (it)?
• Did you find out whether it was me or her who made it?

I would skip referring to "gigabytes" entirely:

How big a hard drive do you need?

And if you are a customer, you ask

What's the biggest drive on the market?

To my (AmE) ears, it seems odd to ask about the number of gigabytes; the thing I'm interested is the size of the drive, and I'd only talk about that until it comes time to specify a number.