Question

Let p: The integer has one digit. Let q: The integer is less than 10. Which represents "The integer has one digit if and only if the integer is less than 10”? p ∨ q p ∧ q p → q p ↔ q

Answer 1

The double implication "if and only if" is graphically represented by an arrow pointing in both direction, so the correct writing is

$p \iff q$