Question:
Who was the chair of United States Department of Energy in May, 2020?

Context:
 Jennifer Granholm is the chair of United States Department of Energy from Feb, 2021 to Dec, 2022. 
 Dan R. Brouillette is the chair of United States Department of Energy from Dec, 2019 to Jan, 2021. 
 Rick Perry is the chair of United States Department of Energy from Mar, 2017 to Dec, 2019.

Answer:
Question:
Who was the chair of United States Department of Energy in May, 2020?

Context:
 Jennifer Granholm is the chair of United States Department of Energy from Feb, 2021 to Dec, 2022. 
 Dan R. Brouillette is the chair of United States Department of Energy from Dec, 2019 to Jan, 2021. 
 Rick Perry is the chair of United States Department of Energy from Mar, 2017 to Dec, 2019.

Answer:
user
Dan R. Brouillette
assistant
Question:
Who was the chair of United States Department of Energy in May, 2020?

Context:
 Jennifer Granholm is the chair of United States Department of Energy from Feb, 2021 to Dec, 2022. 
 Dan R. Brouillette is the chair of United States Department of Energy from Dec, 2019 to Jan, 2021. 
 Rick Perry is the chair of United States Department of Energy from Mar, 2017 to Dec, 2019.

Answer:
user
Rick Perry
Jennifer Granholm
assistant
Question:
Who was the chair of United States Department of Energy in May, 2020?

Context:
 Jennifer Granholm is the chair of United States Department of Energy from Feb, 2021 to Dec, 2022. 
 Dan R. Brouillette is the chair of United States Department of Energy from Dec, 2019 to Jan, 2021. 
 Rick Perry is the chair of United States Department of Energy from Mar, 2017 to Dec, 2019.

Answer:
user
Dan R. Brouillette
assistant