Which hormone is primarily associated with cell division?

If a line in space makes angles $\alpha, \beta,$ and $\gamma$ with the coordinate axes,then the value of $\cos 2\alpha + \cos 2\beta + \cos 2\gamma + \sin^2 \alpha + \sin^2 \beta + \sin^2 \gamma$ is equal to:

Sodium is heated in air at $300^{\circ} C$ to form $X$. $X$ absorbs $CO_2$ and forms $Na_2CO_3$ and $Y$. Which of the following is $Y$?

If $10000\, V$ is applied across an $X$-ray tube, what will be the ratio of the de-Broglie wavelength of the incident electrons to the shortest wavelength of the $X$-rays produced? (Given: $\frac{e}{m}$ for an electron is $1.8 \times 10^{11}\, C\, kg^{-1}$)

Given below are two statements regarding silent heart attack.
Statement $I$: This type of heart attack shows symptoms like chest pain and shortness of breath.
Statement $II$: In this type of heart attack,usually person shows very mild symptoms and thus it is ignored.
In the light of above two statements,choose the correct answer from options given below.

If pairs of straight lines $x^2-2 p x y-y^2=0$ and $x^2-2 q x y-y^2=0$ be such that each pair bisects the angle between the other pair,then