Davies, Charles, 1798-1876 · New York, Cincinnati [etc.] American book company · leaf 189
eheight of a tower standing on the top of an inaccessible hill,there were measured, the angle of elevation of the top of thehill 40°, and of the top of the tower 51° ; then measuring in adirect line 180 feet farther from the hill, the angle of elevationof the top of the tower was 33° 45: required…
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