a) The Sobel operator has two parts as given below Explain the purpose of the two parts of the Sobel operator, and the significa of the edge strength E=Sx2+Sy2. b) The pixel values in the matrix below represent the image of a defect in a digital radiograph. What will be the pixel values of the two highlighted elements after calculation of the edge strength E ? c) Sketch the approximate shape of the original image and the resulting image if the edge strength were calculated for the whole image