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(C) Let $T$ be the set of families with a telephone and $C$ be the set of families with a car.Given: $n(T) = 25\%$,$n(C) = 15\%$,and $n(T^c \cap C^c)

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$2$ and $3$

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(C) Let $T$ be the set of families with a telephone and $C$ be the set of families with a car.Given: $n(T) = 25\%$,$n(C) = 15\%$,and $n(T^c \cap C^c) = 65\%$.By De Morgan's Law,$n(T \cup C)^c = 65\%$,so $n(T \cup C) = 100\% - 65\% = 35\%$.Using the formula $n(T \cup C) = n(T) + n(C) - n(T \cap C)$:$35\% = 25\% + 15\% - n(T \cap C)$$35\% = 40\% - n(T \cap C)$$n(T \cap C) = 5\%$.Statement $1$ says $10\%$ have both,which is false $(5\% 
eq 10\%)$.Statement $2$ says $35\%$ have either a car or a telephone,which is $n(T \cup C) = 35\%$. This is true.Statement $3$: Since $5\%$ of total families $= 2000$,let $N$ be the total number of families.$0.05 	imes N = 2000 \implies N = \frac{2000}{0.05} = 40,000$. This is true.Thus,statements $2$ and $3$ are true.

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