The critical value of t for n=18 and a confidence interval of 95% is

Critical Values 

1.) The critical value of t for n=18 and a confidence interval of 95% is:

a- 1.7396

b- 2.1098

c- 2.5669

2.) The critical value of t for n=7 and a confidence interval of 90% is:

a- 1.9432

b- 2.4469

c- 3.1427

3.) The critical value of t for n=35 and a confidence interval of 95% is:

a- 1.6909

b- 2.0322

c- 2.4411

4.) The critical value of t for n=25 and a confidence interval of 99% is:

a- 2.0639

b- 2.4922

c- 2.7969

5.) The critical value of t for n=79 and a confidence interval of 95% is:

a- 1.9908

b- 2.3751

c- 2.6403

Probability table

1.) The probability of Z = 2.67 is: 

a- .0038 or 0.38%

b- .0029 or 0.29%

c- .0051 or 0.51%

2.) The probability of Z = 0.63 is:

a- .2676 or 26.76%

b- .2643 or 26.43%

c- .2611 or 26.11%

3.) The probability of Z = 0.08 is:

a- .4721 or 47.21%

b- .4681 or 46.81%

c- .4641 or 46.41%

4.) The probability of Z = 0.04 is:

a- .5120 or 51.20%

b- .5160 or 51.60%

c- .5199 or 51.99%

5.) The probability of Z = 1.48 is:

a- .9306 or 93.06%

b- .9292 or 92.92%

c- .9162 or 91.62%