A portable Bluetooth speaker with a 20 Ah battery can supply a constant current of 2 A for 10 hours before it becomes completely discharged. Determine the amount of charge that leaves the battery when the speaker is used continuously until it runs out of charge.

• A. 5.1 × 10⁴ C
• B. 8.2 × 10⁴ C
• C. 7.2 × 10⁴ C
• D. 4.3 × 10⁴ C

Answer: (C)