小阳发现电线杆AB的影子落在土坡的坡面CD和地面BC上(如图所示),

小阳发现电线杆AB的影子落在土坡的坡面CD和地面BC上(如图所示),量得CD8米,BC20米,CD与地面成30º角,且此时测得1米杆的影长为2米,则电线杆的高度为                                                             (    )

   A9            B28          C.(7)米    D.(142)米

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