Part 4 (one point total). For each of the following sequents, provide a proof that demonstrates their validity. You may use the implication rules, but not replacement rules. 1. PVR-PR 2. PVR FRP 3. P&-07-(PQ) 4. -P&-Qt-PvQ) 5. -PV-Q1-(P&Q) 6. (pva) F-P 7. (PVQ) F-P&-Q 8. P&Q=+R, (5-R)&(- Rs), QFPR 9. P&QR, (5 -R)&(-R-S), QP+-5 10. P&QR, (S -R)&(-R->S), QF P&S-M