What is the radius diameter of the following circle?

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

Candy lives in the center of town. her friend darlene lives 28 miles to the east and her friend dana lives 21 miles north. approximately how far do dana and darline live apart ?

Which statement is true about a number and its additive inverse? a. their product is always one. b. their sum is always one. c. they are always reciprocals of each other. d. their sum is always zero.