366.what is the volume of a certain rectangular solid?
(1)two adjiacent faces of the solid have areas 15 and 24,respectively
(2)each of two opposite faces of the solid has area 40
选C 如果说它没告诉是整数所以A不对 (2)的意思是每一对相对面的面积都是40吗
也就是所有面的面积都是40 感觉只有各边长相等才能满足 我选了B
400.is the measure of one of the interior angles of quadrilateral ABCD equal to 60 degrees?
1)two of the interior angles of ABCD are right angles
2)the degree measure of angle ABC is twice the degree measure of angle BCD?
选C 觉得两个和起来也不行 可以得到两个梯形 分别是两个直角 一个45度 一个135度(ABC=90 BCD=45) 和两个直角 一个60度 一个120度(ABC=120 BCD=60) 都满足条件
还请大家指教~ |