Author note — to cover (Higher)

Higher only (G23): area equals half ab sin C with the included angle, no perpendicular height required, run forwards for areas and backwards for a side or angle — G23 explicitly includes all three. Feeds segment-area problems alongside sectors; exact trig values give non-calculator variants. (G23, G21)

• Fluency — direct questions on the area formula ½ab sin c, limited to this lesson's stated scope (4 questions).
• Application — use the same skill in unfamiliar or contextual questions without introducing a later method (4 questions).
• Check — questions built around the exclusions and likely misconceptions named in the lesson brief (4 questions).