A 4-lane road (2 lanes in each direction with no median separation) has a circular curve with a superelevation of 5% and a central angle of 50 degrees. The CT of the curve is at station 5+880 and the Pl is at 5+806. The road has 3.6m lanes and 3.0m shoulders on both sides with high retaining walls going up immediately next to the shoulders (both sides of the road). a) Are the shoulder dimensions adequate according the Austroads Guide to Road Design? Justify your response with a reference to guidance documentation or academic literature. b) Considering speeds in increments of 10km/hr (starting with 40km/hr), what is the maximum safe speed of this curve and what is the station of TC?