Which one of the following is the most widely accepted method of contraception in India,as at present?

Which semi-dwarf variety of plant was developed by Nobel laureate Norman $E$. Borlaug?

$A$ feasible solution to an $LP$ problem,

If $y=\tan ^{-1}\left(\frac{\sqrt{1+a^2 x^2}-1}{a x}\right)$,then $\left(1+a^2 x^2\right) y^{\prime \prime}+2 a^2 x y^{\prime}$ is equal to

Which of the following is a method of sexual reproduction in algae?

Considering only the principal values of the inverse trigonometric functions,the value of $\tan \left(\sin ^{-1}\left(\frac{3}{5}\right)-2 \cos ^{-1}\left(\frac{2}{\sqrt{5}}\right)\right)$ is: