$4.$What does RTD stand for in chemical engineering?

A$)$ Reactor Time Determination

B$)$ Residence Time Distribution

C$)$ Reaction Temperature Determination

D$)$ Reactor Transfer Dynamics

Which curve characterizes the RTD of an ideal stirred$-$tank reactor?

A$)$ C curve

B$)$ E curve

C$)$ F curve

D$)$ Ideal curve

Which type of reactor is most likely to have a uniform RTD$?$

A$)$ Batch reactor

B$)$ CSTR

C$)$ PFR

D$)$ Plug flow reactor

The mean residence time of a reactor is:

A$)$ The time it takes for $50\%$ of the fluid to leave the reactor.

B$)$ The average time spent by fluid elements inside the reactor.

C$)$ The time it takes for the reactor to complete one cycle.

D$)$ The maximum residence time observed in the reactor.