multiple choice:-

STC earnings in billions of Riyals are estimated using GNP (gross national product). The regression equation is where GNP is measured in billions of Riyals.

Interpret the slope.

1. For each additional one billion in GNP, STC earnings on average will increase by .078 billion Riyal.
2. For each additional one billion in GNP, STC T earnings on average will increase by .0.06 billion Riyal.
3. For each additional one billion in GNP, STC T earnings at most will increase by .078 billion Riyal.
4. For each additional one billion in GNP, STC earnings at least will increase by .006 billion Riyal.

If the statistical model for simple linear regression is appropriate, a prediction interval for Y is given by A. b1tSb1 B. YtSf C. ytSf D. XtSf