$7.$ Assign letter grade to each student after above calculations are completed using Vlookup or Hlookup. $(10$ points$)$

$8.$ What is the final grade distributions? In other words, how many students earned A$,$ B$,$ C$,$ D$,$ and F$?$ Use COUNTIF or Pivot Table to organize your data by grade in your excel sheet to show your result. $(15$ points$)$