A sample with size n = 10 has x = 000 0000 500 508.5, and s = 21.5. The dotplot for this sample is given below. 510 520 530 540 550 560 570 Indicate whether or not it is appropriate to use the t-distribution. No If it is appropriate, give the degrees of freedom for the t-distribution and give the estimated standard error. If it is not appropriate, enter-1 in both of the answer fields below. Enter the exact answer for the degrees of freedom and round your answer for the standard error to two decimal places. df = standard error =