Tough nth term Question

I understand (a)(i) and (b)(i) since they are really obvious but the rest literally makes me want to strangle a new-born baby.
In Pattern 2 there are 7 rods, 8 springs and 2 bobs.
In Pattern n there are n bobs.

(i) How many springs are there in Pattern n?
(ii) How many rods are there in Pattern n?

(b) The artist now changes his design to make new patterns with greater widths.The pattern below is called Pattern 3 by 2.In Pattern x by y there are xy bobs.

(i) How many springs are there in Pattern x by y?
(ii) How many rods are there in Pattern x by y?

The answer in accordance to the mark scheme:
(a) (i) 4n
(ii) 3n + 1
(b) (i) 4xy
(ii) Strategy,
e.g. simplify then extend or lookat vertical and horizontal Method leading to correct answer,
e.g. notices 1more row to dimension comparison (x+1)y + x(y+1) ISW (2xy+x+y)

First of all, if it's the 2nd pattern, it's the 2nd term in the sequence. If there are 8 spring rolls, 8/2 = 4... so the nth term will be 4n. If there are 7 rods, it will be 3n+1 as 6+1=7. You could write 4n-1, but it won't work out for the rest of the terms. If you test it:

1st pattern and 2nd pattern using the 3n+1 nth term: ((3 * 1) + 1) = 4 and ((3 * 2) + 1) = 7
1st pattern and 2nd pattern using the 4n-1 nth term: ((4 * 1) - 1) = 3 and ((4 * 2) - 1) = 7
As you can see the numbers were different in the 1st pattern, as the '4n-1' nth term doesn't work.

So, if the current pattern is n. The number of bobs is equal to the pattern number.
So there are n bobs. Using the nth term rule, we can find out the number of springs & rods.
To work out the number of springs; we use: 4n. There is no number, therefore the answer is just 4n. It is the same with the rods, the answer is 3n+1.

You can use the same principle to work out the answer to (b)(i), as the number of bobs is equal to the pattern. If the pattern is x by y, the number of bobs is xy. Therefore, the number of springs will be 4xy, as the nth term is 4n.

I don't really understand (ii) myself, sorry.

I would say the question is a bit ambiguous, if they had given another set of numbers for another pattern, it would have helped.

Yes indeed, it really would.

Are you sure there was no more information

A diagram perhaps?

Yes but it didn't offer much.
Here is the link(question 11):
http://www.jonesthesum.greenhill.pembrokeshire.sch.uk/Ad_maths_-old-_2010_paper_1.pdf

The diagrams answer all your questions you have 3 sets of information for (a) and everything you need for (b)

How do the diagrams give 3 sets of information? I cant see how the diagrams for each pattern give you the number of rods, springs and bobs present in each pattern.

Look at the pattern for 2

Can you see where the 7 rods are, where the 8 springs are, and where the 2 bobs are

It should be obvious

After a good 3 mins and 56 seconds of staring at it, I was able to see it.
And of course I suck.
Thanks a lot.
Oh can you explain how (b)(ii) is done? Just a little bit confused.