HELP please answer all Determine the number of components present in the following system and then calculate the degree

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HELP please answer all
Determine the number of components present in the following
system and then calculate the degree of freedom for the system.
i) NaCl in equilibrium with its saturated solution at
250C and at a pressure of 101.3kNm-2
Answer: 0
ii) CaCl2 in equilibrium with its saturated
solution at 250C and at a pressure of
101.3kNm-2
no answer
iii) I2(s) in equilibrium with
its vapor
Answer:1
iv) I2(s) in equilibrium with
its vapor at 500C
Answer: 0
how do I get the answers using F=C-P+2