Explain the following three itemized questions about Indrect Proof $($a$.$k$.$a$.$ Reductio ad Absurdum$)$:$(1)$ how it works in terms of its unique procedure as a proof, $(2)$ why it constitutes a legitimate proof in spite of its unorthodox procedure by identifying and explaining the two fundamental principles of logic as its underpinnings; and $(3)$why we accept those two principles.