Determine the total charge under each plan for this case: $120$ minutes of day calls and $40$ minutes of evening calls in a month.

Note: Do not round intermediate calculations. Round your answer to $2$ decimal places.

If the agent will only use the service for daytime calls, over what range of call minutes will each plan be optimal?

Note: Round each answer to the nearest whole number. Include the indifference point itself in each answer.

Suppose that the agent expects both daytime and evening calls. At what point $($i$.$e$.,$ percentage of total call minutes used for daytime calls$)$ would she be indifferent between plans A and B$?$

Note: Do not round intermediate calculations. Enter your answer as a percentage rounded to $2$ decimal places. Omit the $"\%"$ sign in your response.