Usonic, Inc., has collected the following information on its cost of electricity:
| Machine Hours |
Total Electricity Costs |
| January |
625 |
$280 |
| February |
700 |
$290 |
| March |
500 |
$265 |
| April |
425 |
$200 |
| May |
450 |
$248 |
| June |
300 |
$170 |
| July |
375 |
$180 |
| August |
550 |
$240 |
| September |
575 |
$260 |
| October |
280 |
$150 |
| November |
430 |
$215 |
| December |
200 |
$100 |
(a) Assuming the line intersects the y-axis at $50 and using the September activity levels calculate the equation of the line that would be drawn for a scattergraph. (Round variable cost to 2 decimal places, e.g. 15.25 and fixed cost to 0 decimal places, e.g 15.)
(b) What is the expected electricity cost when 425 machine hours are used? (Round answer to 2 decimal places, e.g. 125.25.)