①0.5mol NH3 ②标况下22.4L He ③4℃时18mL水 ④0.8mol H3PO4.
A:①④③②
B:④③②①
C:②③④①
D:④③①②
4×7/15=____1÷1/2=____2/3+1/6=____7/8÷7=____52/5+0.3=____
5÷5/3=____1/6×3/8=____3/5-1/2=____0.35+0.4=____8×(12+0.5)=____