$($ a $)$list and explain the different stages followed in new product or service design process $($ b $)$mr shiv kumar a air conditioner repairing person is called for ac repairing and service purpose $.$although he has received extensive training $,$he also relies heavily on his equipments for support $.$during a normal call $,$he uses five essential equipments $,$which reliabilities are $0.98,0.97,0.95$and $0.99,$respectively $.$

mr shiv claims his equipment has a maximum probability of failure of $5\%.$ is he correct?