5、分)下面第()种情况从左面看到的图形是。A. B. C. 四、计算题(共4题;共52分)20.(12分)计算第15页共15页1.02+0.8=________368﹣299=________0.1×0.99=________ + =________0.52﹣0.42=________÷=________1÷0.25=________×=________7.5﹣﹣=________(﹣)×30=________1﹣+=________1÷×2=________.21.(5分)直接写出得数。0.8÷0.2= 457+199