Identify the differential equation for the voltage vd in the circuit shown in the given figure for time t> 0 and A=8. Find an expression for the current ( for time t>0. R, = 20 C= 3F i() V,= AV R, = 60 The current ia is The systems represented by these block diagrams can each be described by a differential equation of the forn S0) *1(-(0) + (1) = -() +aN-1 taz + agy aN %3D For each system, what is the value of N? For each system, what are the a coefficients, starting with aN and going down to ag? In system (b), what range of values of A will make the system stable? The value of A for the given system is 4. x()- The volue of N for the above system is and ap is The velue of the coefficient ag is