SAT coaching: A sample of 10 students took a class designed to improve their SAT math scores. Following are their scores before and after the class. Before After 451 454 453 463 491 511 526 529 473 493 440 466 481 482 459 455 399 404 383 420 Send data to Excel Part: 0 / 2 Part 1 of 2 (a) Construct a 95 % confidence interval for the mean increase in scores after the class. Let d represent the SAT score after taking the class minus the SAT score before. Use the TI-84 calculator to find the critical value and round the answers to at least one decimal place. A 95 % confidence interval for the mean increase in scores after the class is X 5 1