What was the rate at which the glacier's toe retreated (through melting/sublimation) between 1818 and 1882

Explanation:

The missing part of the question is shown in the diagram attached below:

From the image attached, we can see the Map of Rhone Valley glacier in Swiss Alps.

To determine the rate at which the glacier's toe retreated between 1818 & 1882;

Let start by determining the scale of the map

Using the scale of  1.5cm = 3000 feet

Then;

1 cm = 2000 feet

So, if the ice retreated 2.1cm;

Then to feet, we have:

2.1 cm * 2000 feet = 4200 feet

Hence, the required rate at which the glacier toe retreated is:

= 65.63 feet/year

answerthey are called the pampas;

the answer is the last option or letter d)