I find the section difficulty level that rates difficulty of a section on1-5 star scale useful. How is this rating assigned to a section? How many average wrongs make for 1-star and so on..?
For some sections, this difficulty rating seems very off.
PT-71 LG, which is one of the easier LGs, is assigned the same rating as the notorious PT-72 LG (had the surprising pattern game that got most takers) and PT-77 LG (December Lg with two tough games). All of these are given 2-star. Why is that?
Q23
How do we know that Chlorine is the MOST damaging of constituent elements of CFCs?
The passage only says Chlorine is very damaging but no support for it being MOST damaging of CFC elements.