During the 1930’s Paul Robeson committed himself to a life of activism, in which his career as a performer would be secondary. Why did he?

What is the name of the song released by the artist "owl city" in 2009 as a hit single? (it was also one of the dankest memes of 2017)

The description of the house in this excerpt gives an example of

Achair of height 1 m is placed 1 m in front of a plane mirror. a girl is standing 3 m behind the chairas shown. find the minimum length of the plane mirror in order that she can see the whole imageof the chair. a. 0.50 mb. 0.75 mc. 0.80 md. 1.00 m