ASDA interview questions

How would you impove the way you work, tell about yourself, what mistakes you done and how did you learn from it, how would you greet customer , then group assesment with quite easy scenario but always not enough time for my age to respond / I know I have more exerience than yoing people and could do this test well but with young people in the group I have no time to respond because they faster and more assertive and am always behind (( But hey am learning )))