Which of these statements about saltwater is correct?
a. saltwater freezes at a higher temperature.
b. saltwater freezes at a higher temperature
c. saltwater does not freeze at any temperature
d. saltwater's freezing point depends on the temperature of ocean floor

I think one of the statement here is erroneously written since A and B is the same statement. It should be that one choice is that "Saltwater freezes at a lower temperature" and this is the correct answer. Saltwater experiences a freezing point depression due to the salt in the solution.

So  if  the sum of the enthalpies of the reactants is greater than the products, the  reaction  will be  exothermic.  if  the products side has a larger enthalpy, the  reaction  is  endothermic. you may wonder why  endothermic reactions, which soak up energy or enthalpy from the environment, even happen

Ithink that the missing word is mixed