The focal length of the lens to be used to correct myopia when the far point distance is “d” cm. 

Correct option is  C) 2f

Correct option is  B) double

Correct option is  A) -37.5 cm

Correct option is  C) 30 cm

Correct option is  A) 20 cm

Correct option is  C) 40 cm

B) less than 2.5 cm

A) f = 25d/ (d – 25)

 U = -12 f = -10  1/v - 1/u = 1/f 1/v + 1/12 = 1/10 1/v = 1/60  \(-\frac{1}{v^2} \)dv or \(\frac{1}{u^2} \)du du = \(\frac{v^2}{u^2} \)du \( \frac{v}{u} \)= same path △u1 = △u2 = 1mm △u1 = △v2  △v2 = vf - vi  x2 = △v2 + 1mm x2...