1. Which angle is complementary to angle BAC?

A. ACB

Step-by-step explanation:

Complementary angles are two angles whose measures add up to 90°

So BAC + ACB is 90° because ABC is 90° (the total angles of triangle is 180°)

angle ACB

Basic facts:

complementary angles add up to 90 degrees

angles in a triangle add up to 180

Step-by-step explanation:

it is angle ACB because as we can see the triangle is a right-angle triangle

180-90=90

so we can take out angle ABC

therefore angle BAC and ACB add up to 90

B. 2.75 mph

Step-by-step explanation:

If it took him 2 hours to walk 5.5 miles, 5.5 ÷ 2 = 2.75, which is what he walked in a single hour, meaning he was walking 2.75 mph