Problem: Which instrument can separate two liquids by spinning them at high speed?
Answer: centrifuge

Problem: Which US composer wrote the 1976 opera, Einstein on the Beach?
Answer: philip glass

Problem: Sailor Jack and Bingo are the mascots for what prize awarding snack food, now produced by Frito Lay?
Answer: cracker jack

Problem: Which naturalist conceived a theory of natural selection at about the same time that Charles Darwin did so and co-published a paper on the subject with Darwin in 1858?
Answer:
alfred russel wallace