1. **Problem 12:** Calculate distances and times using the speed of light $3 \times 10^{8}$ m/s, expressing answers in standard form. 2. **Formula:** Distance $d = speed \times time$ and Time $t = \frac{distance}{speed}$. 3. **Part a:** Distance light travels in one minute. - One minute = 60 seconds. - Calculate $d = 3 \times 10^{8} \times 60 = 180 \times 10^{8}$. - Convert to standard form: $180 \times 10^{8} = 1.8 \times 10^{2} \times 10^{8} = 1.8 \times 10^{10}$ meters. 4. **Part b:** Time light takes to travel 120 meters. - Calculate $t = \frac{120}{3 \times 10^{8}} = 40 \times 10^{-8}$ seconds. - Convert to standard form: $40 \times 10^{-8} = 4.0 \times 10^{1} \times 10^{-8} = 4.0 \times 10^{-7}$ seconds. **Final answers:** - a) $1.8 \times 10^{10}$ meters - b) $4.0 \times 10^{-7}$ seconds