Which one of the following orders is correct for the bond dissociation energies of halogen molecules?

The decreasing order of bond dissociation energies of $C-C$,$C-H$,and $H-H$ bonds is:

If tangents are drawn from any point on the circle $x^2+y^2=25$ to the ellipse $\frac{x^2}{16}+\frac{y^2}{9}=1$,then the angle between the tangents is

The engine of a jet aircraft applies a thrust force of $10^5 \ N$ during take-off and causes the plane to attain a velocity of $1 \ km/s$ in $10 \ s$. The mass of the plane is:

Which of the following parts of a neuron is covered by a fatty sheath?

$A$ block of mass $2 \ kg$ slides down an inclined plane of inclination $30^{\circ}$. The coefficient of friction between the block and the plane is $0.5$. The contact force between the block and the plane is: