Answer:
(a) decrease in temperature
Step-by-step explanation:
You want to know a possible reason for the weakening of Hurricane Maria as it moves toward the northwest from the Leeward Islands.
Hurricane
A hurricane is a tropical storm fueled by rising warm moist air. When the air is no longer warm or moist, the hurricane loses strength.
As Hurricane Maria moves toward the northwest, the ocean water under it becomes cooler. The decrease in temperature causes the hurricane to weaken.
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Additional comment
Hurricanes rapidly lose strength when they reach land, as there is no source of warm moist air there.