Question

If wind is eroding an area at a rate of 2 mm per year and depositing it in a smaller area at a rate of 7 mm per year, how much lower will the first area be in meters after 2 thousand years? How much higher will the second area be?

Answer 1

Answer:

After 2000 years, the first after will be 4m lower.

After 2000 years, the second area will be 14m higher.

Explanation:

From the given information:

At the first area:

if the wind is eroding at 2 mm/year, then after 2000 years; we have:

2 mm/year × 2000 year = 4000 mm

4000 mm to meters, we have:

$=4000 \ mm \times \dfrac{1 \ m}{ 1000 \ mm}$

= 4 m lower

At the second smaller area:

Given that the wind is depositing it at the rate of 7 mm per year;

Then:

7 mm/year × 2000 year = 14000 mm

$=14000 \ mm \times \dfrac{1 \ m}{ 1000 \ mm}$

=14 m higher