I need help with the following problem: Find the center of mass of the given quarter of a DISK. (25 points)Remember, this disk has surface area and mass density,σMake sure, you show all the procedure to find the xcm and ycm.

Place several e-field sensors at a few points on different equipotential lines, and look at the relationship between the electric field and the equipotential lines. which statement is true? 1-at any point, the electric field is perpendicular to the equipotential line at that point, and it is directed toward lines of higher voltages. 2-at any point, the electric field is perpendicular to the equipotential line at that point, and it is directed toward lines of lower voltages. 3-at any point, the electric field is parallel to the equipotential line at that point.