Question

plzz help me in answering these 2 questions

Answer 1

Answer:

The answer to the question 84 is option 'a'

Explanation:

This is because of the sum of the refractive index which is

10+12 = 22

and 8+10 = 18

so since they have asked is the ratio we will divide both of these terms

so; 22/18= 11/9 or 11:9