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The local authority has been receiving requests from the public to replace a roundabout situated near a medium-density development area with a traffic signal control. Thus, a registration-plate matching study was conducted at this roundabout. The traffic approaching the roundabout from the four legs is as illustrated in Figure 2 below. On-site investigation found that the width of all approaches is 11 m, lane width is 4 m, entry and exit widths are constant at 8 m. As a traffic engineer in the local authority, you are asked to : i. ii. iii. Evaluate and give recommendation whether or not to replace the present roundabout with traffic signals. Determine the capacity of the rotary in East-South direction. Determine the capacity of the rotary in West-North direction. (5 marks) (3 marks) West 14001 370 405 North = 1428 JIL. 505 415 South=1135 403 495 365 595 245 East Figure 2: Traffic movements (in vehicles/hour) at the roundabout