Since its release.

Since its release. Bob Aker's 'Cooking to Go' has sold the following number of copies each Q1:

2X13:200

2X14:430

2X15:530

2X16:450

Using these figures and the equation, y (trend) = 500 + 20x, which of the following is the mean seasonal average of sales of Bob Aker's 'Cooking to Go' for Q1 over the last four years?

Calculate all the final and answer and all intermediate workings to 2 dp.

0.77

0.85

1.02

4.5

0.63