求个C语言编写程序:已知梯形上下底边长和高,求梯形面积答:int main(void) { float upperBase, lowerBase, height;printf("请输入梯形的上底、下底和高: ");scanf("%f %f %f", &upperBase, &lowerBase, &height);printf("梯形的面积为: (%8.4f + %8.4f) * %8.4f / 2 = %8.4f\n", upperBase, lowerBase, height, (upperBase + lower...