Write the ratio as a fraction in simplest form with whole numbers in the numerator and denominator 16 cm to 40 cm

Me because some of question i don’t understand

The distance of a chord from the centre of a circle is 12cm and the lenght of the chord is 10cm. find the radius of the circle

If you have a set of parallel lines a and b cut by transversal x, if angle 1 = 167 degrees, what is angle 4 and why. also what is the measure of angle 5 and why? you need to use the names of the angle relationship and explain.