Can you please help me with these problems? Thank you!

15. The diagram shows, a circuit with a current of 0.16 A through resistor R2. RI 9.00 L = 0.16 A Ri 6.00 150 4.00 Rs 20 0 a) Find the current through resistor R4. b) How much charge flows through the resistor' R4 In 50 s? c) Find the potential difference of the power supply. d) How much energy does resistor R dissipate In 60 s? 16. The diagram shows a circuit composed of four resistors and a power supply. The current through resistor R, Is 2.0 A, and resistor R1 dissipates a power of 16 W. RI WW WW 5.00 L = 0.4A RA WW RIZP, =16W 2.09 Th = 2.0A a) Find the potential difference across R4. . b) Find the resistance of R3. . c) Find the potential difference of the power supply. d) Find the total power dissipated by the resistors