A statistician is following a group of undergraduates. On average, these students drink 4 beers a month, with an SD of 2. They eat 8 pizzas a month, with an SD of 4. There is some positive association between beer and pizza, and the regression equation is

Predicted number of beers = _____________ x number of pizzas + 2

The statistician lost the original data and forgot the slope of the equation. (Perhaps they had too much beer and pizza.) Can you help them remember the slope? If so, show your work and your value for the slope. If not, explain what else you would need to answer this question.