Sorry that it is kind of messy but please read it from the left column first then move to the right column. It is in that order of your questions. For question a part i, please use sine rule and for part ii use cosine rule. For part iii, use the properties of angles on a straight line.

For part b, use sine rule to find the area of the triangle first and since the height of the triangle would be the shortest distance from B to AC, you can find the height with the base of the triangle as AC.

For part C use toa cah soh to solve.

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