5. (20 %) Prove the partial correctness of the following program using the Owicki-Gries method. Variables T, 80, and si are of the same type. T:= {true} acc := 0; T:= 0; := 1; await T +0; await T + 1; So := acc; 11 Si := acc; acc := 30 +1; acc := $1 + 1; T:= 0; T:= 1; {acc =2}