Answer:
It increased demand for shipping and railway transportation.
Explanation:
The Federal-Aid Highway Act of 1956 was famously referred to as the National Interstate and Defense Highways Act. This Act was enacted by the 84th US Congress on the 29th of June, 1956 and signed into law by President Dwight D. Eisenhower.
The effect of the Federal-Aid Highway Act of 1956 include the following;
I. It was used to fund over 41,000 miles of interstate highways in the United States of America.
II. It enabled a faster means of transportation across the United States of America.
III. Freeways were significantly added to cities and as a result of this, it encouraged the growth of suburbs.
