Please Answer b,c,e,f

This is Formal Logic

Exercise 6.3 For each of the following wffs, give a countermodel for every system in which it is not valid, and give a semantic validity proof for every system in which it is valid. When you use a single countermodel or validity proof for multiple systems, indicate which systems it is good for. a)* O[ PO(QR)]0[Q-(OPOR)] b) (PAOQOOP+000) c) (PVOQOPVOQ) d)* O( PQ) (OPHOQ) e) O(PAQ00(OP-OQ) f) (OP+ QO(OPOQ) g)* OOOPHOP h) OOP-OOP i) 0 [(P-OP-OP]+(00P-OP)