(A) I$_2$ (g) $\rightarrow$ 2I (g) is an endothermic process (Atomisation).
(B) HCl (g) $\rightarrow$ H (g) + Cl (g) is an endothermic process (Atomisation).
(C) H$_2$O (l) $\rightarrow$ H$_2$O (g) is an endothermic process (Vaporisation).
(D) C (s) + O$_2$ (g) $\rightarrow$ CO$_2$ (g) is an exothermic process (Combustion).
(E) Dissolution of ammonium chloride in water is an endothermic process (Dissolution).
Thus, the number of endothermic processes is 4.

Find the area of the region \[ R = \{(x, y) : xy \le 27,\; 1 \le y \le x^2 \}. \]
An object of uniform density rolls up the curved path with the initial velocity $v_o$ as shown in the figure. If the maximum height attained by an object is $\frac{7v_o^2}{10 g}$ ($g=$ acceleration due to gravity), the object is a _______

A body of mass $m$ is taken from the surface of earth to a height equal to twice the radius of earth ($R_e$). The increase in potential energy will be ____ ($g$ is acceleration due to gravity at the surface of earth)