Will mark brainliest. which of the following demonstrates how the first 21 (on the left side of the triangle) is calculated using the combination pattern?

What are the measures of ∠a, ∠b, ∠c and ∠d? explain how to find each of the angle measure.

It says factor each expression completely 8y+48

In the diagram, be and ad pass throughthe center of circle o, and the area ofsector aoc is 47.45 square units. what isthe area of sector boc? use the value =3.14, and round your answer to two decimalplaces.22.33 square units25.12 square units