4. Accepting the true null hypothesis is a 5. 1- a is denoted by B, which we call as B. Problem. The Head of Math Dept. announced that the mean grade of Grade 11 students in Algebra is 89 and the standard deviation is 12. One student believes that this mean grade is less than this, randomly selected 34 students and got the mean grade of 85. At 0.01 level of significance, test the student's belief. (20 points) 1. Ho: Ha: 2. Level of significance: 0.01 3. Critical Value: 4. Decision Rule: 5. Computed value: 6. Decision