Which relation is correct for an isochoric process?

The maximum value of $x^4 e^{-x^2}$ is

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

$A$ beam of monochromatic light is incident at $i = 50^{\circ}$ on one face of an equilateral prism. If the angle of emergence is $e = 40^{\circ}$,then the angle of minimum deviation is:

The point of intersection of the lines $l_1: r(t)=(i-6j+2k)+t(i+2j+k)$ and $l_2: R(u)=(4j+k)+u(2i+j+2k)$ is

The approximate value of $(1.0002)^{3000}$ is