Let $A = \{\phi, \{\phi\}, 1, \{1, \phi\}, 7\}$. Which of the following is false?

Two newspapers $A$ and $B$ are published in a city. It is known that $25\%$ of the city population reads $A$ and $20\%$ reads $B$, while $8\%$ reads both $A$ and $B$. Further, $30\%$ of those who read $A$ but not $B$ look into advertisements, $40\%$ of those who read $B$ but not $A$ look into advertisements, and $50\%$ of those who read both $A$ and $B$ look into advertisements. Then the percentage of the population who look into advertisements is:

The domain of $f(x) = \frac{\log_2(x + 3)}{x^2 + 3x + 2}$ is

If $U = \{2, 3, 4, 5, 6, 7, 8, 9, 10, 11\}$,$A = \{2, 4, 7\}$,$B = \{3, 5, 7, 9, 11\}$,and $C = \{7, 8, 9, 10, 11\}$,compute: $(A \cap U) \cap (B \cup C)$.

If ${N_a} = \{an : n \in N\}$,then ${N_5} \cap {N_7} = $

The domain of definition of the function $f(x) = \frac{3}{4 - x^2} + \log_{10}(x^3 - x)$ is