Help me with 23,25 and 26. piecewise and step functions

During your cycling trip, you and your friends often stayed in hostels. the prices of these are listed below. hostel standard room (price per night) with breakfast (price per night) super sleep hostels £22.45 £28.65 normandy nights £18.55 £25 zzzola hostels £24.50 £30.99 belgian beds £11.20 £18.55 night-time rest days ? £33 what is the range in cost for a single night, including both standard room prices and with breakfast prices?

If your teacher tells you to do questions 6 through 19 in your math book for homework, how many questions is that

What ia the sum if the first 7 terms of the geometric series