question: if you want to travel with your pet, you can book this while making the online booking or subsequently up to 48 hours before departure via optional extras » (provided the booking was made via airberlin.com) or at our service center ».
Capitalize this past sentence correctly.
A: If you want to travel with your pet, you can book this while making the online booking or subsequently up to 48 hours before departure via Optional extras » (provided the booking was made via airberlin.com) or at our Service Center ».

question: however, another even smaller study was not removed.
Capitalize this past sentence correctly.
A: However, another even smaller study was not removed.

question: the hotel is 3 km from the vatican and a 25-minute drive from the coliseum. it provides a free hourly shuttle to/from piazza barberini.
Capitalize this past sentence correctly.
A: The hotel is 3 km from the Vatican and a 25-minute drive from the Coliseum. It provides a free hourly shuttle to/from Piazza Barberini.