A phone service provider offers two international plans.
Plan A: $25 per month and 5¢ per minute
Plan B: $3 per month and 12¢ per minute
For what range of minutes of international calls would Plan B be financially advantageous? (Assume the plan will be used for one month. Round your answer up to the nearest whole minute.) Plan B is advantageous if a person places fewer than _______ minutes of international calls per month.
a) 17
b) 18
c) 19
d) 20