Necessary Condition:A necessary condition is a condition that must be true for a given statement or conclusion to be true. If the necessary condition is not met, the statement or conclusion cannot be true.
Logical Implication: Logical implication is the relationship between two statements where if the first statement is true, the second statement must also be true. This is the same as a sufficient condition.
Logical Equivalence: Logical equivalence is a relationship between two statements where if one statement is true, the other statement must also be true, and vice versa. This is a stronger relationship than a sufficient condition.