It was reported in USA Today that from 1999 through 2003 the number of daily spam messages sent worldwide were:

(x) Year Number Date (y) Spam messages sent (billions)

1 1999 1.0

2 2000 2.3

3 2001 4.0

4 2002 5.6

5 2003 7.3

The regression equation was determined to be: y = 1.59 x 0.73

where y is the number of Spam messages sent in billions and x is the Year Number. Using the model what is the predicted number of spam messages sent in 2004?

a) 9.00 billion b) 7.85 billion c) 3,185 billion d) 8.81 billion