Question: Lake Michigan water level records have been kept for many years, showing an overall loss of water over time. The chart below shows depths for various years.

a) Working by hand, find a linear equation that is a reasonable linear model that represents the water level (in feet) t years past 1800. Use the model to predict the water level in 2050.

b) Use linear regression on your calculator to find the best fit linear model for the water level (in feet) t years since 1800. Use the model to predict the water level in 2050.