C I think lol I’m pretty dumb but I heard air has something to do with the sound
Answer:
The Interstate Highway System was launched when President Dwight D. Eisenhower signed the Federal-Aid Highway Act of 1956. Its purpose was to provide high-speed, high-capacity system of highways without stoplights and with exits spaced, whenever possible, at least a mile apart.
The interstate highway system has had a profound effect upon the American economy and contributed significantly to improved economic efficiency and productivity. By increasing speed and expanding access, freight costs have been reduced substantially.
They were intended to serve several purposes: eliminate traffic congestion; replace what one highway advocate called “undesirable slum areas” with pristine ribbons of concrete; make coast-to-coast transportation more efficient; and make it easy to get out of big cities in case of an atomic attack.May 27, 2010
Explanation:hope it help
(x+y)^2=56
x^2+2xy+y^2=56. we know that xy=12
so 2(xy)=24
x^2+24+y^2=56
x^2+y^2=56-24
x^2+y^2=32. <-------------
