The chemical reaction that involves the roasting process is

Apical dominance is caused by

The correct order as indicated in each option is:

$x$ grams of calcium carbonate was completely burnt in air. The weight of the solid residue formed is $28 \text{ g}$. What is the value of $x$ (in grams)?

$A$ plate of thickness $t$ made of a material of refractive index $\mu$ is placed in front of one of the slits in a double-slit experiment. What should be the minimum thickness $t$ for which the intensity at the centre of the fringe pattern is zero?

$\frac{d}{dx}[(1 + x^2)\tan^{-1}x] = $