Amechanical wave is a wave that its energy a) does not require a medium to transfer b) does not transfer c) does require a medium to transfer

C

Step-by-step explanation:

A mechanical wave has to have a medium to work

by definition, an arc subtended by a central angle of some given measure has the same measure. so .

step-by-step explanation:

you can add the two numbers and divide the result by 2. or you can find the gap between the two numbers and add half of this to the smaller number.