Ayuda porfavorrr no entiendo es para un trabajo gracias es de música

What is the missing step in this proof? scroll down to see the entire proof.u

What is it called when someone gets sick from eating food contaminated with germs or toxins? a. potentially hazardous food b. ptomaine poisoning c. foodborne illness d. raw food

The different layers of gases that extend form the surface of the earth into space