This Study Mind Tutorial covers the following specification points:
AQA: 3.1.1.3
OCR: 2.2.1 {a,b(i-iii),c(i,ii),d(i)}
Edexcel: 1.16, 1.17, 1.18, 1,19, 1.20, 1.21(i,ii), 1.23
CIE: 1.3.5, 1.3.6, 1.3.7, 1.3.8, 1.3.9,