Question

plzz help me In solving this question​

Answer 1

Answer:

1/2 is the correct option:)

becoz 1/f=1/(2^2+2-4)

1/f=1/(4+2-4)

1/f=1/2 ....ans

Answer 2

Answer:

I think 1/2 is correct

Step-by-step explanation:

Option d is correct