For \( n \in \mathbb{N} \), the largest positive integer that divides \( 81^n + 20n - 1 \) is \( k \). If \( S \) is the sum of all positive divisors of \( k \), then find \( S - k \).
If water is poured into a cylindrical tank of radius 3.5 ft at the rate of 1 cubic ft/min, then the rate at which the level of the water in the tank increases (in ft/min) is:
A, B, C, D are square matrices such that A + B is symmetric, A - B is skew-symmetric, and D is the transpose of C.
If
\[ A = \begin{bmatrix} -1 & 2 & 3 \\ 4 & 3 & -2 \\ 3 & -4 & 5 \end{bmatrix} \]
and
\[ C = \begin{bmatrix} 0 & 1 & -2 \\ 2 & -1 & 0 \\ 0 & 2 & 1 \end{bmatrix} \]
then the matrix \( B + D \) is:
For a gas in a thermodynamic process, the relation between internal energy (U), the pressure (P), and the volume (V) is given by: \[ U = 3 + 1.5PV \] The ratio of the specific heat capacities of the gas at constant volume and constant pressure is:
Match the following:
List-1: List-2:
A Physical barrier I LysozymeB Physiological barriers II InterferonsC Cellular barriers III MonocytesD Cytokine barriers IV Colostrum V Mucus membrane
If \( A = \begin{pmatrix} x & y & y \\ y & x & y \\ y & y & x \end{pmatrix} \) and \( 5A^{-1} = \begin{pmatrix} -3 & 2 & 2 \\ 2 & -3 & 2 \\ 2 & 2 & -3 \end{pmatrix} \), then \( A^2 - 4A \) is:
When \( Q \) amount of heat is supplied to a monatomic gas, the work done by the gas is \( W \). When \( Q_1 \) amount of heat is supplied to a diatomic gas, the work done by the gas is \( 2W \). Then \( Q:Q_1 \) is: