GreenWealth Incorporated is an investment company whose financial assets grow at a continuous rate of 4%. (Pretend the last year or so didn't happen.) From this must be deducted its expenses?payroll, rent, etc amounting to $200 million per year, which we shall assume has to be paid at a steady, continuous rate.

(a) Let W(t) be the net worth of GreenWealth (that is, assets - expenses) at time t, where t is measured in years and W in millions of dollars. Derive a difierential equation for W(t).

(b) Find the equilibrium solution Weq of the DE, and interpret it in ?financial terms.

(c) Find two solution functions W(t), one with initial value greater than Weq, and one with initial value less than Weq.

(d) Is the equilibrium solution stable?