Author note — to cover

Explain that larger samples give steadier, more reliable estimates, while a badly chosen large sample stays biased; questions compare two proposed samples and justify which is better. Qualitative reasoning only, no margin-of-error or confidence calculations, which are A level. Choosing the selection method sits on the sampling-method pages. Both tiers. (S1)

• Fluency — direct questions on sample size, 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).