Author note — to cover

Areas and perimeters of semicircles and quarter circles: halve or quarter the circle formulas, then add the diameter or two radii whenever a perimeter is asked — the classic omission. Compound shapes with circular parts included. General sector angles move to Arc length and Area of a sector. Both tiers. (G17, G18)

• Fluency — direct questions on semicircles and quarter circles, 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).