Final answer:
The correct expression for the cost of minutes for talking with Plan A is 'Cost = 0.10x + 500', which accounts for the base rate covering 500 minutes and the overage rate of $0.10 per minute for 'x' number of overage minutes.
Step-by-step explanation:
The student has asked for the expression representing the cost of the minutes for talking when 'x' represents the number of overage minutes with Plan A. If the base rate covers 500 minutes and the overage rate is $0.10 per minute, the cost of talking for any overage minutes would be the base rate plus the overage cost. The base rate is a fixed cost, as it covers up to 500 minutes and does not change with the number of minutes used.
Given that overage minutes are charged at $0.10 per minute, the cost of these overage minutes is simply $0.10 times x, where x is the number of overage minutes. Therefore, the total cost would be the base rate cost for 500 minutes plus the additional cost for x overage minutes at $0.10 each. The correct expression for the total cost is Cost = 0.10x + 500, where 0.10 represents the per-minute rate for overage and x represents the overage minutes. This is equivalent to option D in the student's provided choices.