I am working with a graph and if at every 5.6 km you cut in half the atmospheric mass. So at 16.8 km wouldn't you have 12.5% of the atmosphere above and 87.5% would be below?

16.8 = 5.6 x 3, so the mass above 16.8 km decreases to (1/2)^3 = 1/8 or 12.5% of its sea level value.

Your answer is correct

To determine the percentage of the atmosphere above and below a certain altitude, we need to understand how to calculate the cumulative mass distribution of the atmosphere.

In this case, you mentioned that at every 5.6 km, the atmospheric mass is cut in half. This implies an exponential decrease in atmospheric mass with increasing altitude.

To calculate the percentage of the atmosphere above and below a given altitude, we need to consider the cumulative distribution of the atmospheric mass.

Let's first determine the number of halvings required to reach the 16.8 km altitude, which is mentioned in the question:

16.8 km / 5.6 km = 3

Therefore, we require 3 halvings to reach an altitude of 16.8 km.

Now, since each halving represents 50% of the previous mass, we can calculate the percentage of the atmosphere above and below that altitude:

For each halving, the distribution becomes:

50% below, 50% above

After the first halving, we have:

50% below 5.6 km, 50% above 5.6 km

After the second halving, we have:

(50% below 5.6 km) * (50% below 5.6 km) = 25% below 11.2 km and 75% above 11.2 km

After the third halving, we have:

(25% below 11.2 km) * (50% below 5.6 km) = 12.5% below 16.8 km and 87.5% above 16.8 km

So, at an altitude of 16.8 km, we would have approximately 12.5% of the atmosphere below that altitude and approximately 87.5% of the atmosphere above that altitude.