Question

1. $\frac{2,800 \text{kilograms}}{0.915 \text{cubic meters}} cdot \frac{1 \text{cubic meter}}{1.0 cdot 10^6 \text{cm}^3} cdot \frac{1000 \text{grams}}{1 \text{kilogram}}$$\bigcirc$ 1$\bigcirc$ 2$\bigcirc$ 3$\bigcirc$ 45. a star is measured to be 18.9 light years from earth. what is the correct answer in the calculation shown below? (scientific notation.)$18.9 \text{light years} cdot \frac{9.461 cdot 10^{12} \text{km}}{1 \text{light year}} =$$\bigcirc 1.8 cdot 10^{14}$$\bigcirc 1.79 cdot 10^{14}$$\bigcirc 17.9 cdot 10^{13}$$\bigcirc 17.88 cdot 10^{13}$

Explanation:

Step1: Cancel light-year units

$$18.9 \cdot 9.461 \times 10^{12}\ \text{km}$$

Step2: Calculate numerical product

$$18.9 \times 9.461 = 178.8129$$

Step3: Convert to scientific notation

$$178.8129 \times 10^{12} = 1.788129 \times 10^{14}$$

Step4: Round to match options

$$1.788129 \times 10^{14} \approx 1.79 \times 10^{14}$$

Answer:

1.79 $\cdot$ $10^{14}$