Two reactants in a flask at room temperature are producing bubbles of a gas that turn limewater milky. The reactants could be

How many moles of CO can be obtained by reacting $2.0$ mole of ${{\mathrm{CH}}_4}_{}$ with $2.0$ mole of $O_2$according to the equation given below?

${\mathrm{CH}}_3 \left(\mathrm{g}\right) + \frac{1}{2} {\mathrm{O}}_{2\to \mathrm{CO} + 2{\mathrm{H}}_2}$

The position vector of a particle is

$\overrightarrow{\mathrm{r}}-\angle \mathrm{t} \mathrm{x}+3\mathrm{t}\stackrel{\wedge }{\mathrm{y}}+4\stackrel{\wedge }{\mathrm{z}}$Then the instantaneous velocity $\overrightarrow{v}$and acceleration $\overrightarrow{a}$respectively lie