A cost accountant wants to study the cost behavior of financial information and performs a regression analysis on 12 months of data. The dependent variable is overhead costs and the independent variable is machine hours. The co-efficient of determination is 0.83.

Which of the following is true?

I. Machine hours and overhead costs are negatively correlated.

II. The coefficient of correlation is approximately 91%

III. Machine hours account for about 61% of the variation in overhead costs.

IV. Factors other than machine hours account for about 17% of the variation in overhead costs

V. The regression shows a weak correlation between machine hours and overhead costs.