Please provide full explanation

Autosave . rr Q E L?) v C; E] Documentz Home Insert Draw Design Layout References Mailings Review View '3 8 share LU Comments 1 - , 7 V l Lv \""95 New\" V 12 V A 't AaBchDdEe AaBbOchEe AaBchDc AaBchDdEs Bb ) l g _ Paste /, 1 ' , ' Normal No Spat: Hes n91 Head g2 e Styles Dictate m Pane Spam email has become a serious and costly nuisance An ofce manager believes that the average amount of time spent by ofce workers reading and deleting spam is 25 minutes per day The population of times is normally distributed with a standard deviation of 10 minutes To help reduce the amount of time wasted in reading and deleting spam emails, the company installed a very costly spam blocker scware on all computers. To see whether the soware served its purpose, a random sample of 30 workers ms taken and the time each worker spent on reading and deleting spam email was recorded. Mean= 22.9 Standard deviation= 8.322968 a, State the null and alternative hypotheses. bi Can we conclude at the 5% signicance level whether there has been a decrease in mean time spent on reading and deleting spam emails? cl Please state which type of error (Type I or Type II) may be committed here? Consider your conclusion in part (b) oft Page 'I OH 1 : English lU.A E l 7 + l'l4'\