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high grade MEC 4
high grade MEC 3
high grade MEC 2
high grade MEC 1
intermediate grade MEC 6
intermediate grade MEC 5
intermediate grade MEC 4
intermediate grade MEC 3
intermediate grade MEC 2
intermediate grade MEC 1
low grade MEC 17
low grade MEC 16
low grade MEC 15
low grade MEC 14
low grade MEC 13
low grade MEC 12
low grade MEC 11
low grade MEC 10
low grade MEC 9
low grade MEC 8
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