a$)$ The SOURCE of momentum in the differential volume element shown in figure $2\mathrm{.}1d$ as a result of a force, F$,$ applied uniformly to the volume element.

b$)$ The ACCUMULATION of the mass of $A(m_A)$ in the differential volume element shown in figure $2\mathrm{.}1$a$.$

c$)$ The IN$-$OUT terms for the convective transport of the moles of $\text{'}A\text{'}$ in the differential volume element shown in fig $2\mathrm{.}1$b$.$

d$)$ The SOURCE of energy due to an exothermic chemical reaction $($heat of reaction $=H_r,$ reaction rate $=R_{AV}$ in moles$/$vol$-$t$)$ for the differential volume element in figure $2\mathrm{.}1c$

e$)$ The ACCUMULATION of the moles of species A for the differential volume element in figure $2\mathrm{.}1c$

BE SURE TO CLEARLY IDENTIFY THE NOMENCLATURE YOU USE.