Give answers correct to the tenths. a) Use Riemann Sums to approximate area under the curve of f(x)=x^2+1 from 0 to 3 using 3 left rectangles. b)Use Riemann Sums to approximate area under the curve of f(x)=x^2+1 from 0 to 3 using 3 right rectangles. c)Use the sum of the left and right rectangles, find the average area. d)Find the value of the exact area using the integral