Val and Glen have each pledged a certain number of hours to volunteer for their community. The graph shown compares the numbers of volunteer hours remaining for Val and Glen over time, in weeks.
Volunteer Hours
у
25
20
Val
Hours Remaining
15
10 Glen
5
0
1 2 3 4 5
Time (weeks)

Find the measure of the interior angles of the following regular polygons: a triangle, a quadrilateral, a pentagon, an octagon, a decagon, a 30-gon, a 50-gon, and a 100-gon.

Sanya noticed that the temperature was falling at a steady rate of 1.4 degrees every hour from the time that she first checked her outdoor thermometer. by 6 a.m., the temperature had fallen 21 degrees. which expression can you use to find how many hours earlier she had first checked the thermometer?

Solve the following simultaneous equation by using an algebraic method (either substitution or elimination) 2x + 3y=-4 4x-y=11