The most likely reason for the development of resistance against pesticides in insects damaging a crop is

The $AT/GC$ ratio in human beings is (where $A=$ adenine,$T=$ thymine,$G=$ guanine,$C=$ cytosine).

$A$ particle of mass $M$ is at a distance $a$ from the surface of a thin spherical shell of uniform mass $M$ and radius $a$. Which of the following statements is true regarding the gravitational field and potential inside the shell?

The reagent used in the Wolff-Kishner reduction is

In which one of the following do male and female gametophytes not have a free-living independent existence?

If $f: R \rightarrow R$ is defined by $f(x)=x-[x]-\frac{1}{2}$ for $x \in R$,where $[x]$ is the greatest integer not exceeding $x$,then $\{x \in R: f(x)=\frac{1}{2}\}$ is equal to :