Answers:
b = 92 degrees (choice B)
c = 92 degrees (choice D)
d = 92 degrees (choice F)
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Step-by-step explanation:
Angles a and b are supplementary because they form a straight angle when combined. The two angles add to 180
a+b = 180
88+b = 180 ... plug in a = 88
b = 180-88 ... subtract 88 from both sides
b = 92
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Angles b and c are congruent because they are alternate interior angles. Alternate interior angles are congruent when dealing with parallel lines.
Since the diagonal entrance ramps are parallel, this means the corresponding angles c and d are congruent.
Since b = 92, this means c = 92 and d = 92 also.