题目

   核电站中可用硼酸(H3BO3)吸收中子,阻断核辐射。则硼酸中硼元素的化合价是 ( ) A.+1          B.+2         C.+3        D.+4 答案:CYesterday I talked to Amy on the phone and she ______ happy.A. lookedB. soundedC. smelledD. tasted 
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