Answer:
B. least 2°; greatest 178°
Explanation:
The measure of ∠ADC will be the sum of the measures of the two acute angles ADB and BDC.
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Each acute angle with a measure that is a whole number of degrees will have a measure between 1° and 89°, inclusive.
The least sum of two such angles will be ...
1° +1° = 2°
The greatest sum of two such angles will be ...
89° +89° = 178°