A Resistor Is Connected to an Ideal Ac Power Supply

A resistor is connected to an ideal ac power supply.
(a) The phase angle between the current and voltage is
A) 0
B) π/2 radians.
C) -π/2 radians.
D) π radians.
E) 3π/4 radians.
(b) The current in the resistor
A) leads the voltage across the resistor by 90°.
B) lags the voltage across the resistor by 90°.
C) is in phase with the voltage across the resistor.
D) the voltage across the resistor by 45°.
E) lags the voltage across the resistor by 45°.
(c) How does the average power dissipated in the resistor change as the frequency in the ac power supply decreases?
A) It decreases.
B) It increases.
C) It does not change.
D) It increases or decreases depending on the sign of the phase angle.