Question

1 point
29.If the power of a lens is -2.5 D,
then calculate its focal length.
1.-20 cm
2.-30 cm
3.- 40 cm
4.+ 40 cm​

Answer 1

Answer:

I think it's option (c)

Explanation:

because power is equal to the reciprocal of the focal length of the lens.

hope it helped

thank you.

Answer 2

How many oranges should she sell for 112 rupees to gain 20% on the whole? so, 21 oranges should she sell for rupees 112 to gain 20% on the whole.