Answer the following questions step by step. I am in first year university so please keep solutions to that level. Thanks

Question 1 (15 points) Continuity/Differentiability The cost, in thousands of dollars, of a 30-second television ad during the super Bowl in the years 1980-2010 can be approximated by the following piecewise-linear function ( 1 = 0 represents 1980): 43.9t + 222 if0 Sts 20 C(t) = 140t -1, 700 if20 20 1-20* Question 2 (10 points) Rates of change Rising sea levels, in mm, fit the following curve: 1000 1000 where s(t) =-0.002t- + 3t +6; Ost= 125 . Here t=0 corresponds to the year 1900. a) Determine the average sea level increase during the last century. (3 points) b) Determine the derivative of the function s (t) . (5 points) c) Determine the sea level increase at the turn of the 21st century. (2 points)