A circuit consists of a 10F capacitor connected in series with a 25 k2 resistor with a switchable 100V d.c. supply. When the supply is connected, calculate (a) the time constant, (b) the maximum current, (c) the voltage across the capacitor after 0.5s, (d) the current flowing after one time constant, (e) the voltage across the resistor after 0.1 s, (f) the time for the capacitor voltage to reach 45 V and (g) the initial rate of voltage rise.