The horizontal and vertical displacements $x$ and $y$ of a projectile at a given time $t$ are given by $x = 6t \text{ m}$ and $y = 8t - 5t^2 \text{ m}$. The range of the projectile in metres is

One and a half mole of oxygen combine with aluminium to form $Al_2O_3$,then the weight of aluminium metal used in this reaction is ............. $g$ (Atomic weight of $Al = 27$)

Which of the following is a conjugate acid-base pair?

$A$ $100 \ mL$ solution of $0.1 \ N$ $HCl$ was titrated with $0.2 \ N$ $NaOH$ solution. The titration was discontinued after adding $30 \ mL$ of $NaOH$ solution. The remaining titration was completed by adding $0.25 \ N$ $KOH$ solution. The volume of $KOH$ required for completing the titration is $............ \ mL$.

The distribution of a random variable $X$ is given below:

$X = x$	$-2$	$-1$	$0$	$1$	$2$	$3$
$P(X = x)$	$\frac{1}{10}$	$k$	$\frac{1}{5}$	$2k$	$\frac{3}{10}$	$k$

The value of $k$ is:

$C_2H_6 \stackrel{450^{\circ}C}{\longrightarrow} C_2H_4 + H_2$. The above reaction is called: