1. The problem asks to convert the speed of light from kilometers per second (km/s) to centimeters per second (cm/s) and express the result in standard form. 2. We know the speed of light is given as $300\,000$ km/s. 3. To convert kilometers to centimeters, use the conversion factors: - $1$ km = $1,000$ meters - $1$ meter = $100$ centimeters 4. Therefore, $1$ km = $1,000 \times 100 = 100,000$ cm. 5. Multiply the speed in km/s by $100,000$ to convert to cm/s: $$300,000 \times 100,000 = 30,000,000,000$$ 6. Express $30,000,000,000$ in standard form: $$30,000,000,000 = 3 \times 10^{10}$$ 7. Final answer: The speed of light in cm/s is $3 \times 10^{10}$ cm/s.