Don't understand the process of this stats question

"A factory buys 10% of its components from supplier A, 30% from supplier B and the rest from supplier C. It is known that 6% of the components it buys are faulty.

Of the components bought from supplier A, 9% are faulty and of the components bought from supplier B, 3% are faulty.

a) find the percentage pf the components bought from supplier C that are faulty

A component is selected at random
b) Explain why the event 'the component was bought from supplier B' is not statistically independent from the event 'the component is faulty'."

So what my issue is, is that I don't understand the process behind these questions. I was thinking it had something to do with Binomial Distribution and etc. but still didn't understand on how I could actually apply it to this question.
It would really help on finding out how I can answer questions like these in the future, thanks.

Have you done part (a)? Try that first.

I don't wanna come off as a prick but that's a yikes from me man

Like I don't know how to do the question man

I don't wanna come off as a prick but that's a yikes from me man

Like I don't know how to do the question man

Apologies for the late reply
I made a 3-way tree diagram with:

Supplier A on top (10%) - 9% Faulty, 91% normal
Supplier B in the middle (30%) - 3% Faulty, 97% normal
Supplier C on the bottom (60%) - x% faulty, (100-x)% normal

So apparently this "adds up" to an overall 6% and I'm overall confused on how that works unless I (obviously) am missing something.