Extracted text: 3 A masonry dam 21m high, has a triangular cross section. The upstream side being vertical. The masonry weighs 23.544 kN/m". The water depth at the upstream side of the dam is 18m. Calculate the width of the base of the dam if the resultant reaction at the base is located 4/10 B from the toe. Round off your answer to a whole number. Answer: B = m 21m 18 m B = ?