The number of circles that touch all the straight lines $x+y=4$,$x-y=-2$,and $y=2$ is

What is the use of Guayule ($Parthenium$ $argentatum$)?

The Young's modulus of a wire is $Y$. If the energy per unit volume is $E$,then the strain will be

Assertion : Cattle breeds can be improved by super ovulation and embryo transplantation.
Reason : Superovulation in high milk-yielding cows is induced by hormonal injection.

An organ pipe $P_1$ closed at one end is vibrating in its first overtone. Another pipe $P_2$ open at both ends is vibrating in its third overtone. They are in resonance with a given tuning fork. The ratio of the length of $P_1$ to that of $P_2$ is:

$\frac{d}{dx}[(1 + x^2)\tan^{-1}x] = $