Your roommate is working with a protein that takes substrates and ejects them out of a cell (a molecular pump/shuttle). You arrive one day to find them hunched over their desk trying to make sense of data associated with an experiment they performed on their protein. Worried, you ask them if they need help and they tell you they need to calculate the concentration of pump-bound molecules in their system or they wont be able to sleep!As a generous and masterful Biochem student, you offer to help them. You tell them their reaction can be summarized as follows: P + S ßkR -- kF PS kT P, since the substrate is ejected from the cell in the final step and can be ignored.A. You decide to first provide them with expressions for d[P]/dt, d[S]/dt, and d[PS]/dt. What would those be?B. Assuming a steady state in [PS] over time (d[PS]/dt=0), provide them with an expression for [PS] as a function of [Ptot], [Stot], kF, kR, and kT, where [Ptot]=[PS]+[P] & [Stot]=[PS]+[S].