In your own words, explain what the null hypothesis is.2. What are Type I and Type II Errors?3. What is ?4. Why do we phrase null and alternative hypotheses with populationparameters and not sample means?5. If our null hypothesis is "H0: = 40", what are the three possible alternativehypotheses?6. Why do we state our hypotheses and decision criteria before we collect ourdata?7. When and why do you calculate an effect size?pg. 1478. Determine whether you would reject or fail to reject the null hypothesis inthe following situations:a. z = 1.99, two-tailed test at = 0.05b. z = 0.34, z* = 1.645c. p = 0.03, = 0.05d. p = 0.015, = 0.019. You are part of a trivia team and have tracked your team's performancesince you started playing, so you know that your scores are normallydistributed with = 78 and = 12. Recently, a new person joined the team,and you think the scores have gotten better. Use hypothesis testing to see ifthe average score has improved based on the following 8 weeks' worth ofscore data: 82, 74, 62, 68, 79, 94, 90, 81, 80.10.You get hired as a server at a local restaurant, and the manager tells you thatservers' tips are $42 on average but vary about $12 ( = 42, = 12). Youdecide to track your tips to see if you make a different amount, but becausethis is your first job as a server, you don't know if you will make more orless in tips. After working 16 shifts, you find that your average nightlyamount is $44.50 from tips. Test for a difference between this value and thepopulation mean at the = 0.05 level of significance