Final answer:
The total cost of renting a bike for 4 hours is $42.
Step-by-step explanation:
To find the total cost of renting a bike for 4 hours, we need to calculate the additional cost for each hour rented and add it to the upfront fee. The additional cost per hour is $7. So for 4 hours, the additional cost would be $7 x 4 = $28. Adding the upfront fee of $14, the total cost would be $14 + $28 = $42.