During the World War Ⅱ, Leonard Bloomfield and C. C. Fries applied theories and ideas of behaviourism and structuralism systematically to foreign language teaching and devised a new approach called______.

A．the Direct Method

B．the Oral Approach

C．the Audiolingual Method

D．the Cognitive Approach

已知X为FeO和CuO的混合物，取两份等质量的X样品进行如图所示实验

（1）写出第③步反应的离子方程式：__________________________

（2）实验中从第③步所得固体D的质量为32g，溶液E中只含有一种金属离子，气体F在标准状况下的体积为5．6L。试计算取用的每份X中FeO和CuO的质量比。