President Reagan "sign" refers to the removal of barriers that divided East and West Berlin, Germany. In his speech made in West Berlin on 12th June 1987, the U.S President Ronald Reagan asked the leaders of Sovie Union to open up the barrier that divided East and West Berlin in his speech "Tear down this wall"
Answer: to prevent the spread of slavery to any territory won from Mexico during the war.
Explanation: The end of the 1840s saw the Congress battling the issue of whether to permit slavery in the territories organized in any new land acquired from Mexico and as such, during the Mexican-American war, Congressman David Wilmot introduced the Wilmot Proviso, which was a proposal to ban slavery in any new territory acquired from Mexico and although the measure passed in the House of Representatives it failed in the Senate. As such, the main purpose of the Wilmot Proviso was to prevent the spread of slavery to any territory won from Mexico during the war
Currently, the only mandatory responsibility of a US citizen from this list would be "to serve on a jury if called," although in the past, military service has been mandatory as well.
A .OPEC began an oil embargo of the United States.
