Final answer:
Protests against the Vietnam War took place in April and May 1968 in various locations in the United States, including Kent State University and Washington D.C.
Step-by-step explanation:
In April and May 1968, protests against the Vietnam War occurred in various locations in the United States. One notable protest took place at Kent State University in Ohio, where four students were tragically killed by National Guard troops. Another significant protest occurred in Washington D.C., where thousands of demonstrators marched on the Pentagon to express their opposition to the war. Additionally, there were protests on college campuses across the country and at other locations, such as public squares and government buildings.