I'm so stuck on this exercise, my mind can't handle wordy problems very well. Any ideas on how to translate this into understandable math? :

"""One morning it started to snow, and the snow fell steadily for the rest of the day. At
noon a snowplow started to clear a road at a constant rate in terms of the volume of snow removed per hour. The snowplow had cleared 2 km by 2 o’clock and 1 more km by 4 o’clock. When did it start snowing?""" !math

(it's so stupid because I feel like this should be elementary)