$A$ wooden block, with a coin placed on its top, floats in water as shown in the figure. The distances $l$ and $h$ are shown. After some time, the coin falls into the water. Then:

If $(2,3,-3)$ is one end of a diameter of the sphere $x^2+y^2+z^2-6x-12y-2z+20=0$, then the other end of the diameter is

Two masses of $10\,kg$ and $20\,kg$ respectively are connected by a massless spring as shown in the figure. $A$ force of $200\,N$ acts on the $20\,kg$ mass. At the instant when the $10\,kg$ mass has an acceleration of $12\,m/s^2$ towards the right,the acceleration of the $20\,kg$ mass is: (in $,m/s^2$)

In Whittaker's classification system,which kingdom acts as the primary producer?

If $p$-th,$q$-th,and $r$-th terms of a geometric progression are the positive numbers $a, b,$ and $c$ respectively,then the angle between the vectors $(\log a^2) i + (\log b^2) j + (\log c^2) k$ and $(q-r) i + (r-p) j + (p-q) k$ is

An observer moves towards a stationary source of sound with a speed $1/5^{th}$ of the speed of sound. The wavelength and frequency of the source emitted are $\lambda$ and $f$ respectively. The apparent frequency and wavelength recorded by the observer are respectively: