13. smoke exhaled from a smokers longs is called mainstream smoke .
true or false

i believe the answer would be 'd'.

hope this !

starvation is bad because your body needs nutrition and to deprive it of nutrition can cause problems with both health and fitness.

explanation:

it can make weight loss slow down over time, but it won't cause someone to gain weight depsite restricting calories. starvation causes weakness in the senses like thirst.