Absorption and adsorption are respectively

Assertion $(A)$: Adsorption is an exothermic process.
Reason $(R)$: Physisorption of a gas on a solid surface is normally reversible.

The correct statement regarding chemisorption is

Which of the following statements is incorrect for physical adsorption?

The correct option$(s)$ related to adsorption processes is(are):
$A$. Chemisorption results in a unimolecular layer.
$B$. The enthalpy change during physisorption is in the range of $100$ to $140 \ kJ \ mol^{-1}$.
$C$. Chemisorption is an endothermic process.
$D$. Lowering the temperature favors physisorption processes.

$3 \, g$ of activated charcoal was added to $50 \, mL$ of acetic acid solution $(0.06 \, N)$ in a flask. After an hour,it was filtered and the strength of the filtrate was found to be $0.042 \, N$. The amount of acetic acid adsorbed (per gram of charcoal) is: .............. $mg$