The problem figure shows the top view of an object. Identify the correct elevation from amongst the answer figures looking in the direction of the arrow.
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Read the top view as a base platform, a middle block that is nearest to the observer, and two taller blocks behind it; draw only the edges that are visible.
The top view shows an outer rectangle (the base platform), a large rectangle attached to the left edge (a block standing on the platform), and a small rectangle at the right that overlaps the large block on its left part and reaches the right edge of the platform. The line at the right end of the large block crosses the small rectangle, so the small rectangle is made of two parts of equal height: one standing on the large block and one standing on the platform. The observer looks up the page, so the platform front edge is the nearest, then the large block, and the small rectangle lies behind the large block. The elevation therefore has: a full-width base strip (platform) with its top line across the whole width; the large block above it, as wide as the large rectangle only (from the left edge to about three quarters of the width), with its top line complete because it is in front; behind it, two tall parts: one above the large block and one at the right on the platform, the right one being lower by the height of the large block. Since the large block is in front of the left tall part, the left edge of the left tall part ends at the top of the large block and is not drawn down to the ground, while the common vertical line between the two tall parts is continuous from the top to the platform line. Comparing with the answer figures: figure 1 draws the left edge of the tall part down to the platform (a hidden edge), figure 2 extends the top line of the large block over the full width, and figure 3 has an extra horizontal line across the tall parts. Figure 4 has no such defect. Answer: (4) the fourth answer figure
