题目

阅读下面短文，在空白处填入1个适当的单词或括号内单词的正确形式,答案写在答题卡上。Withoutthe usual smoggy days, local (resident)have been happy with the air quality since the heating season started. Theyopen the window to air their homes. In social media, pictures of blue skies andwhite clouds (frequent)appear, (show) people's excitement withthe clear days.InShanxi, major coal production province, burning coarsecoal(粗煤)for heating used to be a main sourceof air (pollute). The government has been striving tochange all this. It has launched a campaign t10、已知x^(m-n).x^(2n+1)=x^11(x≠0，x≠1），且y^(m-1).y^(4-n)=y^5(y≠0，y≠1).求mn^2的值。