An independent random sample is selected from an approximately normal population with unknown standard deviation. Find the degrees of freedom and the critical t value tâtâ for the given sample size and confidence level. Sample size, n Confidence level Degree of Freedom Critical value, tâtâ
5 90
13 95
22 98
15 99

Ascientist has 50 grams of a radioactive element. the amount of radioactive element remaining after t days can be determined using the equation (1) after two days the scientist receives a second shipment of 50 grams of the same element. the equation used to represent the amount of shipment 2 remaining after t days is 10) - 50 which of the following is an equivalent form of the expression for the amount remaining in shipment 2? what’s the answer?