Which of the following plants is known for its hallucinogenic properties?

The coefficient of $x^4$ in the expansion of $\frac{(1-3x)^2}{(1-2x)}$ is equal to

If the length of the tangent from $(h, k)$ to the circle $x^2+y^2=16$ is twice the length of the tangent from the same point to the circle $x^2+y^2+2x+2y=0$,then

An electron is projected along the axis of a circular conductor carrying current $I$. The electron will experience:

$2 \pi - (\sin^{-1} \frac{4}{5} + \sin^{-1} \frac{5}{13} + \sin^{-1} \frac{16}{65})$ is equal to

The sound waves of wavelengths $5 ~m$ and $6 ~m$ produce $30$ beats in $3 ~s$. The velocity of sound is: (in $~m/s$)