How many sides does a regular polygon have if one exterior angle is 90 degrees? 3 4 5 6?

4 sides

B is correct

Step-by-step explanation:

A regular polygon has each exterior angle is equal.

The sum of all angle of exterior angles of regular polygon is 360°

For given regular polygon each exterior angle is 90°

Let use n number of side of polygon or n exterior angles.

Total sum of exterior angles = 90n

It must be equal to 360° because sum of all exterior angles.

90n = 360°

    n = 4

Hence, The number of sides of regular polygon whose each exterior angle 90° is 4

where is the gragh

step-by-step explanation:

a mantle plume is an upwelling of abnormally hot rock within the earth's mantle. as the heads of mantle plumes can partly melt when they reach shallow depths, they are thought to be the cause of volcanic centers known as hotspots and probably also to have caused flood basalts.

step-by-step explanation: