6.1 - Pythagoras - Calculating a hypotenuse
6.2 - Pythagoras - Calculating a shorter side
6.3 - Pythagoras - Mixed problems
6.4 - Introduction to trigonometry
6.5 - Trigonometry - missing lengths (unknown in numerator)
6.6 - Trigonometry - missing lengths (unknown in denominator)
6.7 - Trigonometry - missing lengths (mixed)
6.8 - Trigonometry - missing angles
6.9 - Trigonometry - mixed problems