Which main area of the americas is an isthmus

The Main Area of the Americas that is an isthmus is Central America.

Explanation:

If you check a map the part that connects the two land masses of south america and north America is called an isthmus and whats on that isthmus is Central America because its the middle connecting it hence the name

the causes of the dust bowls were severe droughts,   lands became dry and hard, temperature was higher than usual, hot and dry conditions killed crops, high winds. because of those factors, the winds kicked up dry soil and created clouds of dust.

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