Which would be considered a secondary source about the assassination of Abraham Lincoln? a diary entry by a witness to the assassination
an interview with a member of the audience at Ford’s Theater where Lincoln was shot
an interview with Booth’s understudy, who was not at Ford’s Theater the night of the assassination
a newspaper article written by a reporter who was in the audience at Ford’s Theatre

An interview with Booth's understudy

Explanation:

Secondary source is an article or paper talking about a thing, Without seeing it happen. For example, You have someone who saw Abraham Lincoln get shot. Then they write down what happened. The thing they wrote down is a primary source. Your friend tells you what happened in Ford's Theater, but he wasn't actually there. Thats a secondary source. Hope this helps, I spend 15 minutes typing this :)

the industrial revolution pushed the world into modern industrialization. it changed the course of history profoundly. it caused rapid urbanization and pushed cities and countries into development. the industrial revolution began in great britain with a series with new inventions which led to the creation of machines and mass production.

this caused the country to gain wealth and money and become an international superpower. it improved transportation and manufacturing inside the country, pushed people to live in urban areas and britain to become the most powerful nation in the world for a while.

roosevelt believed that in light of the country's recent military successes, it was unnecessary to use force to achieve foreign policy goals, so long as the military could threaten force. this belief, and his strategy of “speaking softly and carrying a big stick,” shaped much of roosevelt's foreign policy.