Answer: The freezing point depression is 
Explanation:
Depression in freezing point is given by:
= Depression in freezing point
= freezing point constant =
m= molality =
Thus freezing point depression is 
It was loss of nutrients, I think
Explanation:
The quarry was dug up and vegetation started dying. The quarry was probably rich with nutrients
Please brainliest !! ❤️
Reactivity trends of halogen:
1) Melting point and boiling points increased down the
group
2) Colour becomes darker.
E.g. Fluorine (pale yellow)
Chlorine (yellowish-green)
Bromine (reddish-brown)
Iodine (purplish-black)
Astatine (black)
3) The reactivity decreases down the group.
Reactivity:
F > Cl > Br > I > At