Please help me revise my answer...I couldn't find any ways on how to answer this question...I already have my answer on question number 4 but my teacher, she said it needs revision and I don't know how..please help me solve this. It's about STATISTICAL INFERENCE FOR TWO SAMPLES

This is my answer on question number 4:

4. Is there an improvement in the performance in English of female pupils from Razque Sikat Elementary School from First to Second Grading? (Hint: Use actual grades in English for the comparison) Female ist 2nd D pupils Quarter Quarter 1 91 25 2 35 3 83 80 9 10 76 315 MEAN 81.5 1. H : D=0 2. Hi: D=0 (two-tailed) 3. 0 =0.05 (by default) 4. Test Statistic: T with n-1 =9 degrees of freedom Critical value for T at 0.05 level (two-tailed) and v=9 dfare -2.262 and +2.262 5. Computations: = 52 - 1/10 (-18) + 10-1 n - = 52 - 0.1 (-324) =9 = 19.6:9 = 1.47573 al.8 + 1.47573 / (square root of 10) 0.46666680115 er. 0.46667 1.6 : 0.4667 =-3.857 Conclusion: Since the result of to = 3.857, reject the null hypothesis. There an improvement in the performance in English of female pupils from Basque Sikat ES from First to Second GradingData: Performance of Grade VI pupils in two elementary schools in Mama North District (Cervantes, 2007) RESP GRADING SCHOOL SEX MATH ENGLISH AVERAGE 20 90 90_0 85 86.0 81 81.0 78 79_0 79 77 78.0 77 76 76.5 87 88.0 86 36.5 85 85.5 84 84.5 83 83.5 82 82.5 81 81.5 80.5 80.0 78 79_0 76 76.0 85 34.5 82 81.0 79 79_0 79 78.5 85 85.0 84 84.0 83 83_0 83 82.5 83 82.0 81 80.5 80 30_0 91 91.5 28 89_0 35 85.0 81 81.5 79 79_0 79 79_0 78 78.0 91 90 5 88.5 87 88.0 84 34.0 84 83.5 82 82.0 81 81.5 80 80.5 79 79 5 77 77.5 85 85.0 19 82.520 79 79 79_0 21 79 79 79_0 22 36 86.0 86 85.5 24 84 84.0 25 83.5 26 81 82.0 27 80 80.5 28 80 80.5 Coding: SCHOOL: 1 -Bagong Sicat E.S.; 2 -Estrella Village E.S. // SEX: 1 -boy; 2-girl