A software package created by Navarro & Associates can be usedfor analyzing and designing three-sided guyed towers and three- andfour-sided self-supporting towers. A single-user licence willcost 546 per year. A site licence has a one-time cost of$15,000. A structural engineering consulting company is trying todecide between two alternatives: first, to buy one single-userlicence now and one each year for the next 4 years (whichwill provide 5 years of service); or second, to buy a site licencenow. Determine which strategy should be adopted at an effectiveinterest rate of 9% per year for a 5-year planning period, using the present worth method of evaluation.