A:农业在国民经济中的基础地位将逐渐被弱化
B:工业在国民经济中的主导地位将逐渐被取代
C:第三产业的就业吸纳能力将逐步增强
D:第一、第二产业就业人口都将绝对减少
(Ⅰ)若f( π6 )=2,求a的值;
(Ⅱ)若f(x)在 π12 , 7π12 上单调递减,求f(x)的最大值.
— It seems that Mr. Wu is standing there.— It ______ be him because he called me from Canada just now.