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A circuit is constructed with four resistors, one capacitor, one battery and a switch as shown. The values for the resistors are: R1 = R2 = 22 ?, R3 = 90 ? and R4 = 129 ?. The capacitance is C = 40 ?F and the battery voltage is V = 12 V. The positive terminal of the battery is indicated with a + sign.

1) The switch has been open for a long time when at time t = 0, the switch is closed. What is I4(0), the magnitude of the current through the resistor R just after the switch is closed?

2) What is Q(?), the charge on the capacitor after the switch has been closed for a very long time?

3) After the switch has been closed for a very long time, it is then opened. What is Q(topen), the charge on the capacitor at a time topen = 785 ?s after the switch was opened?

4) What is IC,max(closed), the current that flows through the capacitor whose magnitude is maximum during the time when the switch is closed? A positive value for the current is defined to be in the direction of the arrow shown.