一批同样的圆木堆成一堆，其横截面是梯形，上层有8根，下层有14根，一共堆成7层，这批圆木一共用多少根？9c0b9T5Q'h
算式：提示)T+I9a(c6t5x1?/x.t,G5v:D'R9c0b9T5Q'h
答：这批圆木一共用8u;b0J/u-F0s:L;l1I9\-m4P2`9z根。9c0b9T5Q'h