Question

plz answer this five questions

Answer 1

Ans(1)- A negative exponent just means that the base is on the wrong side of the fraction line, so you need to flip the base to the other side. For instance, "x–2" (pronounced as "ecks to the minus two") just means "x2, but underneath, as in 1 x 2 \frac {1}{x^2} x21 ".
Ans(2)-The power of a lens is the measure of its ability to converge or diverge a parallel beam of light on refraction through it .Negative sign for Concave lens and Positive sign for Convex lens. The S.I.unit of power is dioptre