Step-by-Step Solution
Key Concept: The contrapositive of an implication is logically equivalent to the original statement.
Let $p$: my friends come, $q$: we go for picnic, $r$: weather will be fine. The statement is $p \rightarrow (q \wedge r)$. The contrapositive is $(\neg (q \wedge r)) \rightarrow \neg p$, which simplifies to $(\neg q \vee \neg r) \rightarrow \neg p$. This means: if my friends do not come or we do not go for picnic then weather will not be fine.
Correct Answer: F