4. (10 painta) Starko. (a) (3 poitita) Camplete the folloning Jwn clas fur a atak mine the adapter vesies pattem (b) (2 points) Explain in plain English (not psendocode or Java) how to ue a stack $ (imitially empty) to teverse. an array of n different char's. (c) (3) points) Pestfir nofation is an unambicuous way of writing arithmetic expressions without the need for pareathesis. A normal parenthesized (cxpi) op (erp? ). woukd le writen as paph perp, op, where op is the perp2 are their eguivaleat expresions tranelatical inte pout tix tutation, reqpectively. For example. - "4+5" tranalates 10=17+in joutfix notatiois. whili of bow to mse a stack to phtse and enuluabe the atithinet is exprtsain