The population of blue whales in a certain region was 540 in…

The population of blue whales in a certain region was 540 in 2015 and 610 in 2018.   Assume that the population of blue whales continues to increase according to a linear model.   a.  Estimate the number of blue whales in 2035.  Round your final answer to the nearest whole number. b.  In what year will the number of blue whales exceed 1500?  Show all work.