If the charge on the capacitor is increased by $2 \ C$,the energy stored in it increases by $21 \%$. The original charge on the capacitor is: (in $C$)

$A$ sample of a radioactive element has a mass of $10 \, g$ at an instant $t=0$. The approximate mass of this element in the sample after two mean lives is ........ $g$.

$A = \{x_1, x_2, x_3, x_4\}$; $B = \{y_1, y_2, y_3, y_4\}$. $A$ function $f: A \to B$ is defined. The number of one-one functions such that $f(x_i) \neq y_i$ for $i = 1, 2, 3, 4$ is equal to:

Which of the following biomolecules is common to respiration-mediated breakdown of fats,carbohydrates and proteins?

The equation of a straight line passing through the point $(1,2)$ and inclined at $45^{\circ}$ to the line $y=2x+1$ is

If $\frac{2 x^3+x^2-5}{x^4-25}=\frac{A x+B}{x^2-5}+\frac{C x+1}{x^2+5}$,then $(A, B, C)$ equals to