Python Write a function that calculates a cell phone bill
First screenshot of rules and such
Second screenshot is example of outcome

print("welcome to the bill calculator")

minutes = float(input("number of minutes you used: "))

data = float(input("the amount of data you used in GB: "))

print("your basic plan costs $39.99 per month")

mcost = (minutes - 450) * .45

print("you will be charged " +  str(mcost) + " for the minutes you used")

print("the monthly data fee is $30.00")

dcost = (data - 3) * 10

print("you will be charged " + str(dcost) + " for the extra data you used")

total = mcost + dcost + 69.99

print("your total bill is " + str(total))

the 20 value your teacher gave may be incorrect, bc 4.2-3*10 = 12 not 20, making the total 109.89

i'm pretty sure data is stored in a form