Bottleneck

Here if i compare required hours with available both of them seems as bottleneck but answer says otherwise

We obviously do not know how many of each product they actually end up producing because we do not have more information. However at the extremes, if they were to only produce Product A then Department A could produce 600/10 = 60 units whereas Department B could produce 930/15 = 62 units. So in this case Department A would be the bottleneck. If, on the other hand, they were to only produce Product B, then Department A could produce 600/20 = 30 units whereas Department B could produce 930/20 = 46.5 units. So again Department A would be the bottleneck. Therefore whatever ends up happening, it is Department A that is the bottleneck.

I got this. But in Sep 16 exam , 11th question its pretty much the same detail. There if i have to identify which is bottleneck we compare hours required with hours available and decide that process 2 is bottleneck. I was wondering why we cant apply that here ?

Can you kindly help me with this statement as well :Work in progress should be valued at material cost that no value will be added to profit until the sale takes place. i know the assumption that material is only variable. but rest of the statement i cant understand

It is the same as for the normal valuation of inventories in that they should be valued at cost not at selling price. Profit only arises when the goods are actually sold and not while they are still in inventory.