(also Known as th of Calculus ) ! (2) Let's consider the definite integral 2 2 + e= ) dz. (a) Draw (with your hands or a computer) a picture of the area this definite integral rep- resents. Your picture does not need to be "to scale", but the general shape should be accurate. (b) What kind of Riemann sum will definitely result in an underestimate of this area? (c) Using the type of Riemann sum you chose in part (b) and 3 subintervals, estimate this definite integral. d) Using the definition of the definite integral, write down an exact expression for this definite integral. (Note: you do not need to "solve" or "simplify" this expression!)