①0.42×15=
②5.2×0.8=
③1.37×0.21≈(得数保留一位小数)
④2.16×8=
6.86×0.74= 12÷0.24= ☆0.755÷0.28≈ (得数保留两位小数)
9.9×4.950 15.6×2.11.56×21
0.84÷1.20.84 7.53×1.017.53÷1.01