A.

Population must follow the normal distribution.

B.

The standard deviation must be known.

C.

It is not necessary to make any assumption about the shape of the population.

D.

The data must be at least interval scale.

A.

Its shape is based on the sample size.

B.

It is not negative.

C.

It is positively skewed.

D.

It approaches a normal distribution as the degrees of freedom increase.

A.

9.488

B.

11.070

C.

43.773

D.

None of the above.

A.

All the cell frequencies must be the same.

B.

There must be at least 30 observations.

C.

Forty percent of the cells must contain at least 10 observations.

D.

None of the above.

A.

The number of rows must be the same as the number of columns.

B.

A variable is classified according to two criteria.

C.

There must be at least 10 observations in each cell.

D.

All of the above.