I will give the brainiest Tonya's dog-walking service charges a flat rate of $20 per month, plus $3 per mile that each dog is walked. Beth does not charge a monthly fee for her dog-walking service, but she charges $5 per mile that each dog is walked. Select the equation and solution to find the number of miles m for which Tonya and Beth would charge the same amount.
A. 8m = 20
B. m = 10
C. 20 + 3m +5m=0
D. 20 + 3m = 5m
E. m = 12
F. m=2.5