Which of the following statements is incorrect?

Degenerate electron pressure will not be sufficient to prevent core collapse of a white dwarf if its mass becomes $n$ times the solar mass. The value of $n$ is:

Two blocks of masses $10\,kg$ and $4\,kg$ are connected by a spring of negligible mass and placed on a frictionless horizontal surface. An impulse gives a velocity of $14\,m/s$ to the heavier block in the direction of the lighter block. The velocity of the centre of mass is ......... $m/s$.

The number of subsets of $\{1, 2, 3, \ldots, 9\}$ containing at least one odd number is

What is obtained from yeast?

Emulsification of $10 \, mL$ of oil in water produces $24 \times 10^{18}$ droplets. If the surface tension at the oil-water interface is $0.03 \, J \, m^{-2}$ and the area of each droplet is $12.5 \times 10^{-16} \, m^2$,the energy spent in the formation of oil droplets is $.... \, J$.