Determine the criticаl vаlue (z) fоr the fоllоwing: Lаst year, when the iPhone 14 was released, AT&T found that 32% of current iPhone users chose to upgrade. Economists predicts that the percent of current iPhone users that will upgrade to the iPhone 15 Platinum will be different. In a sample of 300 current iPhone users, 81 said they planned to or already had upgraded to the newest iPhone. Test the claim using α=.06{"version":"1.1","math":"α=.06"}.