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In the diagram, bc¯¯¯¯¯∥de¯¯¯¯¯ . what is ce ? enter your answer in the box.

Acentral angle measuring 160 degrees intercepts an arc in a circle whose radius is 4. what is the length of the arc the circle formed by this central angle? round the length of the arc to the nearest hundredth of a unit. a) 4.19 units b) 6.28 units c) 12.57 units d) 12.57 square units

Find the measure of angle a in the following triangle