What can congress do if the president vebes a bill?

By threatening a veto, the President can persuade legislators to alter the content of the bill to be more acceptable to the President. Congress can override a veto by passing the act by a two-thirds vote in both the House and the Senate. (Usually an act is passed with a simple majority.)

Explanation:

what the first or next guy says

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.