In "marian anderson sings," how are fiorello laguardia, the mayor of new york city, and eleanor roosevelt, first lady of the united states, similar?   a. they both resign from the dar in protest.   b. they both object to the way the dar treats marian anderson.   c. they both offer to pay anderson if she agrees to sing at constitution hall.   d. they both offer marian anderson other arenas to sing in.