user: Question: What is Ensemble Name MuxCo Gloucestershire's Advertisement Date in Block 10C?
Columns: ['Area', 'Advertisement date', 'Block', 'Winning applicant', 'Ensemble name']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['Hertfordshire , Bedfordshire and Buckinghamshire', 'December 2006', '10D', 'NOW Digital', 'NOW Home Counties']
SQL:

assistant: SELECT "Advertisement date" FROM "Table" WHERE "Block" = '10C' AND "Ensemble name" = 'MuxCo Gloucestershire';