the figure shows cross-section of a ruler which is a rectangle of 2. 5 cm by 0.2 cm on which surmounted an isosceles trapezium (one in which the non- parallel sides area of equal length). the shorter of the parallel sides of the trapezium 0.7 cm long.if the greatest height of the ruler is 0. 4 cm and it is 33 cm long,calculate its surface area