What are the different types of BCI tools?

Idon’t understand 8. plz ! we are finding the area of polygons. thx in advance!

Which of these statements properly demonstrates the angle addition postulate for the m∠afc m∠afc ? a. m∠afc=m∠afb+m∠bfd m∠afc=m∠afb+m∠bfd b. m∠afc=m∠afb+m∠bfc m∠afc=m∠afb+m∠bfc c. m∠afc=m∠cfd+m∠dfe m∠afc=m∠cfd+m∠dfe d. m∠afc=m∠afb+m∠dfc+m∠cfb m∠afc=m∠afb+m∠dfc+m∠cfb

You find a mysterious, dull substance on the ground and pick it up for a closer look. it is powdery, very light, and soft to the touch. the substance is most likely i. an organic mineral ii. a metallic mineral iii. a nonmetallic mineral i only ii only iii only i and ii i and iii