Probability of standard normality corresponding to 1. (63-56)/ 10=.7 is 0.758, greater than 1-0.39=0.6 1, which is acceptable.

2. The average value is 48, and the sample difference is 5.6/sqrt {25} = 5.6/5 =1.12.

95% confidence space [48-1.96 *1.12,48+1.96 *1./2] = [48-2.

99% confidence space [48-2.57 * 1. 12, 48+2.57 *12] = [48-2.8784, 48+2.8784]

= [45.1216,50.8784] .3./Yes.

4./ Odd time