*Hint* Assume **S** and derive **R ∨ P** from 1st premise. Now two sub-proofs, for **∨**-elim: 1) Assume **R** and derive **Q ∨ R** by **∨**-intro, and it is done. 2) Assume **P** and derive **¬R → Q** from 2nd premise. Now use **R ∨ ¬R** (Excluded Middle) for a new **∨**-elim: 2.1) Assume **R** and derive **Q ∨ R**. 2.2) Assume **¬R** and derive **Q** from **¬R → Q** and derive **Q ∨ R**. Having derived **Q ∨ R** in each case, we can conclude with: >**S → (Q ∨ R)** by **→**-intro.