There's a distinction between the <em>address </em>of the cell and the <em>value</em> it contains, and the difference in this problem lies in that distinction. The <em>contents</em> of cell 5 are the value 8, so moving that to cell number 6 would set its value to 8 as well, which is clearly different from the value 5.
500=4πr^2. first divide 500 from four which will equal 125, then divide 125 with π and it will equal 39.788 . finally √39.788. the answer will be r=6.3 or 6
