Acompany found that new employees prefer training sessions of moderate length; shorter training sessions provided too little instruction to complete a task, while longer training sessions contain too much instruction to remember. for a training session on a particular task, the company determined that the ratings new employees gave for the training session could be approximated by upper r (t )equals startfraction 30 t over t squared plus 225 endfraction comma where t is the length of the training session in minutes. find the training session length that received the highest rating.