What was the 1947 law that sought to reverse gains made by organized labor in the preceding decade, and authorized the president to suspend strikes by ordering an eighty-day cooling-off period, banned sympathy strikes and secondary boycotts, outlawed the closed shop, and authorized states to pass "right to work" laws

The correct answer to this open question is the following.

The Taft-Hartley Act was the 1947 law that sought to reverse gains made by organized labor in the preceding decade and authorized the president to suspend strikes by ordering an eighty-day cooling-off period, banned sympathy strikes and secondary boycotts, outlawed the closed shop, and authorized states to pass "right to work" laws.

The act was bad news for union laborers in the United States. Although the US President Harry S. Truman vetoed the legislation on June 20, 1947, trying to considering the demands of the workers, the US Congress override the decision and the act became a law on June 23. Representative Fred A. Hartley was the Congressman who introduced the act that was widely supported by Republicans and Democrats.

b) race riots in several cities