A mobile phone company has introduced a pay-as-you-go price structure, with three possibilities. Plan 1: $10 a month 10 cents per minute Plan 2: $15 a month 7.5 cents per minute Plan 3: $30 a month 5 cents per minute (a) Construct a table in Excel showing the total cost for one month for each of the three plans. (b) Use Excel to draw on chart showing how the monthly bill (y-axis) depends on the number of minutes you use the phone (x-axis) for all three plans. (c) Write a paragraph explaining to your friend how they should go about choosing the plan that is best for them