What is the measure of an interior angle of a regular 9-gon?​

Both the red and blue line segments stretch from the center of the circle to a point on the circle. the length of the blue segment is 5. how long is the red line segment?

Apatient is to be given 35 milligrams of demerol every 4 hours. you have demerol 50 milligrams/milliliter in stock. how many milliliters should be given per dose?

What is the perimeter of an equilateral triangle if each side is (x+3)?