What is the cytoskeleton composed of?

The coefficient of $x^{24}$ in the expansion of $(1+x^2)^{12}(1+x^{12})(1+x^{24})$ is

If the direction ratios of two lines are given by $3lm - 4ln + mn = 0$ and $l + 2m + 3n = 0$, then the angle between the lines is:

The circumcentre of the triangle with vertices at $(-2, 3)$,$(1, -2)$ and $(2, 1)$ is

$A$ plane passes through the point $A(2, 1, -3)$. If the distance of this plane from the origin is maximum,then its equation is:

The tyre of a bicycle has a volume of $2 \times 10^{-3} ~m^3$. Initially,the tube is filled to $75 \%$ of its volume with air at an atmospheric pressure of $10^5 ~Nm^{-2}$. When a rider is on the bicycle,the area of contact of the tyre with the road is $24 \times 10^{-4} ~m^2$. The mass of the rider with the bicycle is $120 ~kg$. If a pump delivers a volume of $500 ~cm^3$ of air in each stroke,then the number of strokes required to inflate the tyre is $\left(g=10 ~ms^{-2}\right)$.