The problem figure shows the top view of objects. Looking in the direction of the arrow, identify the correct elevation, from amongst the answer figures.
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Treat the top view as five blocks seen from the arrow side: nearer blocks hide the lower part of the blocks behind them, so no hidden edge may be drawn.
The top view shows five rectangular blocks inside a square. The arrow points up the page, so the observer stands below the bottom edge and looks upward: the block at the bottom of the plan is nearest, then the lower-left block, then the centre block, and the top-left and top-right blocks are farthest. Left to right, the horizontal order of the blocks is: top-left block and lower-left block (left side), bottom block (centre-left), centre block (centre-right) and top-right block (right side). Neighbouring blocks overlap in width, so in the elevation they overlap and the nearer block must be drawn in front. The farther a block is, the taller it is in the correct elevation, so the heights step down towards the observer. Because a nearer block is in front of a farther one, every vertical edge of a farther block is drawn only down to the top of the nearer block that covers it, and is never carried down to the ground. Check the answer figures: in the first figure the left edge of the tall right-hand block runs down to the ground through the centre block, which shows a hidden edge; the third figure has extra lines and a split block in the front cluster, and in the fourth figure an edge continues through the nearest block. The second figure has all edges stopping at the top of the block in front, the five overlapping widths in the right proportions, and the nearest block fully drawn. Answer: (2) the second answer figure
