【正确答案】：解:内表面抹混合砂浆:(30-0.24)2+(15-0.24)×4×2.8-1.2×1.5×8-1.2×2×3=310.37m2
柱面抹水泥砂浆:3.1416×2×2.8=17.59m2
外墙外表面抹水泥砂浆:(30.24+15.24×2×3.1-1.2×1.5×8-1.2×2+2×(1.2+1.5)×0.24×8+(1.2+2×2)×0.24=276.79m2
墙面嵌缝:(30.24+15.24)×2×3.1=281.98m2