The equations of the tangents to the circle $x^2 + y^2 = 13$ at the points whose abscissa is $2$,are

The coefficient of $x^{10}$ in the expansion of $(2+3x)e^{-x}$ is

In an atom,the order of increasing energy of electrons with quantum numbers $(i)$ $n=4, l=1$,$(ii)$ $n=4, l=0$,$(iii)$ $n=3, l=2$,and $(iv)$ $n=3, l=1$ is:

Which crop developed by mutation breeding shows resistance to yellow mosaic virus?

$A$ body of mass $2 \, kg$ moving with a velocity of $3 \, m/s$ collides head-on with a body of mass $1 \, kg$ moving in the opposite direction with a velocity of $4 \, m/s$. After the collision,the two bodies stick together and move with a common velocity. What is the common velocity in $m/s$?

$A$ particle executes simple harmonic oscillation with an amplitude $a$. The period of oscillation is $T$. The minimum time taken by the particle to travel half of the amplitude from the equilibrium position is