Choice A is the correct answer. Solve $100(0.92)^t = 50$.

1. Simplify: $(0.92)^t = 0.5$.
2. Test Values:
   • $t=8$: $(0.92)^8 \approx 0.51$ (above 0.5)
   • $t=9$: $(0.92)^9 \approx 0.47$ (below 0.5)
3. Conclusion: Answer is between 8 and 9 hours.

💡 Strategic Tip: For SAT, estimation and testing values is often faster than logarithms.

Choice B is incorrect because 50 is the target percentage, not the time. Choice C is incorrect because the decay is too slow for this short time. Choice D is incorrect because by hour 10, battery would be below 50%.