Related Clues:

• ''Why, certainly!''
• Unfailing
• 'Excellent!'
• Concurrence
• 'Awright!'
• Da, somewhere
• Free from doubt
• -
• ''I knew it!''
• Pro vote
• With 45-Across, emphatic assent
• 'That'd be fine'
• 'Why not?!'
• Slangy OK
• One-third of a Beatles refrain