Question 4a is on construction of a triangle given the perimeter, base and a base angle. To solve the problem use geometrical means to subtract the base from the perimeter, then bisect the other line of the triangle to locate the third point of the triangle as shown below. A good number of the candidates got the solution correctly

4a

Question 4b is on isometric drawing from two given views. The first step is to draw isometric axes or isometric box . locate the lowest point and take suitable measurements. The solution is given below. A good number of the candidates attempted the question, majority of whom did well.

4b