Which of the following has the most acidic proton?

When the engine is switched off,a vehicle of mass $M$ is moving on a rough horizontal road with momentum $p$. If the coefficient of friction between the road and the tyres of the vehicle is $\mu_k$,what is the distance travelled by the vehicle before it comes to rest?

Kangaroo rat is found in:

The half-life period of a radioactive element $X$ is the same as the mean life time of another radioactive element $Y$. Initially,they have the same number of atoms. Then:

If the circle $x^2+y^2=a^2$ intersects the hyperbola $xy=c^2$ in four points $(x_i, y_i)$,for $i=1, 2, 3, 4$,then $y_1+y_2+y_3+y_4$ equals

Which of the following compounds exhibits a dipole moment?