Two IT consulting firms have different pricing structures. TechMind charges $115 per hour, plus an upfront fee of $250 for booking an appointment. RiddleBreak doesn't charge for booking an appointment, but the rate is $160 per hour. Let Ci(t) and Cy(t) be the costs, in dollars, of consulting t hours by TechMind and RiddleBreak respectively. (a) Write down expressions for the costs of consulting, C, and C2, in terms of the number of hours, t, charged.
(b) Find the least number of whole hours of consulting from TechMind for its services to be a cheaper option.