Context: Mark Z. Jacobson, professor of civil and environmental engineering at Stanford University and director of its Atmosphere and Energy Program says producing all new energy with wind power, solar power, and hydropower by 2030 is feasible and existing energy supply arrangements could be replaced by 2050. Barriers to implementing the renewable energy plan are seen to be "primarily social and political, not technological or economic". Jacobson says that energy costs with a wind, solar, water system should be similar to today's energy costs.

Question: Who is a professor of civil and environmental engineering at Stanford University?
Answer: Mark Z. Jacobson

Question: What is a barrier to implementing the renewable energy plan?
Answer: social and political

Question: Who stated that energy costs with a wind, solar, water system should be similar to today's energy costs?
Answer: Mark Z. Jacobson

Question: Jacobson says producing all new energy with wind power, solar power and hydropower is feasible by what year?
Answer: 2030

Question: Who is a professor of English at Stanford University?
Answer: Unanswerable

Question:  What is a barrier to implementing the non-renewable energy plan?
Answer: Unanswerable

Question: Who stated that energy costs with a wind, solar, water system should not be similar to today's energy costs?
Answer: Unanswerable

Question: Jacobson says producing all new energy with wind power, solar power and hydropower is not feasible by what year?
Answer: Unanswerable