4.0 points possible (graded, results hidden) Consider the following grammar. S AB1 A + BAB | ABB B0|A| Answer the following questions based on the grammar above. 1. Which of the following variables are nullable? B S 2. After removing the nullable/epsilon productions, which of the following grammars can be derived? S + AB1|B1|A1|1 A + BAB|AB|B|BA B70A O S + AB1|B1|A1|1 A + BAB|AB|B|BB|BA B +0A O S + AB1|B1|A1|1 A + BAB|AB|B|BB B0A O None of the above