PLZ HELP Find the circumference and the area of a circle with diameter 4cm.
Use the value 3.14 for π, and do not round your answers. Be sure to include the correct units in your answers.

Which sum or difference identity would you use to verify that cos (180° - q) = -cos q? a.) sin (a -b) = sin a cos b – cos a sin b b.) cos (a -b) = cos a cos b – sin a sin b c.) cos (a -b) = cos a cosb + sin a sin b d.) sin (a + b) = sin a cos b + cos a sin b