Replacing old equipment at an immediate cost of $5000 and $7000 six years from now will result in a savings of $3000 semi-annually for ten years.

Replacing old equipment at an immediate cost of $5000 and $7000 six years from now will result in a savings of $3000 semi-annually for ten years. At 11% compounded annually, should the old equipment be replaced?a) Should be replacedb) Should not be replacedc) Neither** Please include formula, and show your work to receive Best Answer - so I understand how you reached your answer.  Thank You