A中含____较多,B中含____较多,C中含____较多.
David was so excited at the good news that he could __________ say a word.
一个铜球的质量是178g,体积是40cm3,判断这个铜球是空心的还是实心的?如果是空心,则空心部分体积多大?如果给空心部分灌满水,则球的总质量是多大?(ρ铜="8." 9×103kg/m3)
(Ⅰ)求C;
(Ⅱ)若c= 7 ,△ABC的面积为 332 ,求△ABC的周长.