Please help me!!!!

The function R(x) billion dollars models revenue from new-car sales for franchised new-car dealerships in the United States when x million dollars are spent on associated advertising expenditures, data from 1.2 S x S 6.5.+ (a) Use R(2.5) = 147 and R'(2.5) = 36 to write the function for a linearization model with respect to x at c = 2.5, where x million dollars are spent on associated advertising expenditures, with data from 1.2 s x 5 6.5. R ( x ) = billion dollars (b) Use the linearization model to estimate the revenue when $1.6 million is spent on advertising. LA billion (c) Use the linearization model to estimate the revenue when $2 million is spent on advertising. billion