Pupil is the answer, it changes according to the light it recives
The answer is B. The specific heat means the heat amount the substance needs to absorb when the temperature increases 1℃. The high specific heat means that it needs a huge amount of heat when increase just 1℃. For A, the dissolved salts can help decrease the freezing point.
Answer:
c.building immunity towards diseases
Smoking ruins your lungs making it harder to breath and get oxygen
you need oxygen when you exercise so you don't faint
smokers get less so it is harder for them, its like trying to exercise while breathing through a sponge or a straw os