20. Nuclear fusion in the Sun is increasing its supply of: (A) neutrons (B) helium (C) positrons (D) hydrogen (E) nucleons

10. In an oscillating series RLC circuit with R = 50 Ω, L = 20 mH and C = 2.0 μF, the maximum charge is stored on the capacitor at t = 0. Find the time required for the charge on the capacitor falling to 37% of its initial value. (A) 1. × 10⁻⁴ s (B) 2. × 10⁻⁴ s (C) 4. × 10⁻⁴ s (D) 6. × 10⁻⁴ s (E) 8. × 10⁻⁴ s