The units digit of 1623 is 6, since 6 is in the units digit of the base.
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The units digit of 7148 is 1, since 1 is in the units digit of the base.
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The units digit of 5961 is 9, since 9 is in the units digit of the base and the exponent is an odd interger.
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Sum of all unit places = 6 + 1 + 9 = 16
Units place of the result = 6
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