Question

a plate moves 200 m in 10,000 years. what is its rate in cm/year?
0.02 cm/year
2 cm/year
10 cm/year
100 cm/year

Explanation:

Step1: Recall rate formula

Rate is distance divided by time, so \( \text{Rate} = \frac{\text{Distance}}{\text{Time}} \).

Step2: Convert units (if needed)

Distance is 200 m. Convert meters to centimeters: \( 200\ \text{m} = 200\times100 = 20000\ \text{cm} \). Time is 10,000 years.

Step3: Calculate rate

Substitute into the formula: \( \text{Rate} = \frac{20000\ \text{cm}}{10000\ \text{years}} = 2\ \text{cm/year} \).

Answer:

2 cm/year (corresponding to the option "2 cm/year")