Question:
Who was the chair of BT Group in Mar, 2009?

Context:
 Sir Christopher Bland is the chair of BT Group from Jan, 2001 to Jan, 2007. 
 Jan du Plessis is the chair of BT Group from Nov, 2017 to Dec, 2022. 
 Sir Michael Rake is the chair of BT Group from Jan, 2007 to Nov, 2017.

Answer:
Question:
Who was the chair of BT Group in Mar, 2009?

Context:
 Sir Christopher Bland is the chair of BT Group from Jan, 2001 to Jan, 2007. 
 Jan du Plessis is the chair of BT Group from Nov, 2017 to Dec, 2022. 
 Sir Michael Rake is the chair of BT Group from Jan, 2007 to Nov, 2017.

Answer:
user
Sir Michael Rake
assistant
Question:
Who was the chair of BT Group in Mar, 2009?

Context:
 Sir Christopher Bland is the chair of BT Group from Jan, 2001 to Jan, 2007. 
 Jan du Plessis is the chair of BT Group from Nov, 2017 to Dec, 2022. 
 Sir Michael Rake is the chair of BT Group from Jan, 2007 to Nov, 2017.

Answer:
user
Jan du Plessis
Sir Christopher Bland
assistant
Question:
Who was the chair of BT Group in Mar, 2009?

Context:
 Sir Christopher Bland is the chair of BT Group from Jan, 2001 to Jan, 2007. 
 Jan du Plessis is the chair of BT Group from Nov, 2017 to Dec, 2022. 
 Sir Michael Rake is the chair of BT Group from Jan, 2007 to Nov, 2017.

Answer:
user
Sir Michael Rake
assistant