Final answer:
James Brolin played both Dr. Steven Kiley in 'Marcus Welby, M.D.' and John in 'Life in Pieces.'
Step-by-step explanation:
The question requires identifying actors from specific television shows. Dr. Steven Kiley is a character from the television show Marcus Welby, M.D., which aired from 1969 to 1976. The actor who played Dr. Steven Kiley was James Brolin. In contrast, the character named John from the show Life in Pieces, which aired from 2015 to 2019, is also played by James Brolin. Therefore, the correct responses to the question are: a) Dr. Steven Kiley for Marcus Welby, M.D. and b) John for Life in Pieces.