Not sure why a CIPD course needs this info, but it's an interesting (and surprisingly difficult) exercise in trying to find out commercial info.
CAPA (Centre for Aviation) has a 2013 article which gives a lot of figures and one very relevant graph at the end. See
https://centreforaviation.com/insigh...exposed-111132
The key graph shows that BA in May 2013 has 14.3% of Business/First seats and a further 3.8% in World Traveller plus. It's percentage of First/Business seats is the second highest after Emirates.