The following 1997-2007 data reflects current year's US dollars/Yen exchange rate and level of US exports to Japan in billions of dollars.Assume the correct functional form is linear.

Exchange Rate	US Exports to Japan	Year
121.1	68.6	1997
131	57.8	1998
113.7	57.5	1999
107.8	64.9	2000
121.6	57.5	2001
125.2	51.5	2002
115.9	52	2003
108.2	53.6	2004
110.1	54.7	2005
116.3	58.5	2006
117.8	61.2	2007

1.Does the current value of the US/Yen exchange rate influence the current value of US exports to Japan?Based on this information which variable is the independent and which is the dependent variable.

P.S I don't know how to set the denpendent and independent variables.how to decide? what's exact meaning of R2.

thanks.