Answer:
The answer is 2.14 cm/yr
Step-by-step explanation:
To calculating Sea Floor Spreading
The formula to follow is: Rate of Spreading = distance the sea floor moved / length of time
or R = d/t
Generally expressed as cm/yr
1 km = 1000 m
1 m = 100 cm
so 1 km = 100,000 cm or 10^5 cm
To calculate the real distance that the plate has moved over the past 280 million years,
Given that we have 6,000km, Hence: we convert kilometers to centimeters
Therefore 6000km = 600,000, 000 cm = 6 * 10^8 cm
Then, determine the length of time that the plate has been moving
280 million years = 280,000,000 years = 2.8* 10^8 years
Use the above equation to calculate spreading rate
R = d/t or R = 6 * 10^8 cm / 2.8* 10^8 years = 2.14 cm/yr