What influence do the following facts have on the validity of the relevant contract?

(a) ) Sifiso enters into an agreement with Battery centre that he buys a new battery for his car in terms of an instalment sale transaction. Battery Centre is under the impression that the battery is supplied as a rental unit.

(b) Maria wants a new carpet. She is allergic to any synthetic material, she must purchase a carpet that is made of leather. Barry sells her a carpet that is made of synthetic material. Barry tells her that the carpet is pure leather. The carpet was delivered on 20 March 2020. The next day Maria wakes up with bumps all over her body and the doctor diagnosed it as an allergic reaction to synthetic material. Upon investigation, it turned out that that the carpet was not pure leather as Barry informed her