Classify each pair of angles as one of the following

In the diagram of circle o, what is the measure of zabc?

What is the geometric mean of 3 and 7? a) square root of 21 b) 2 square root of 6 c) 2 square root of 7 d) 21

Grandpa ernie is shrinking! over the past 4 years his height decreased by a total of 2.4 cm.it decreased by the same amount each year. what was the change in grandpa ernie's height each year