Need help cant solve

5. You have decided to order a large pizza from Dominos for dinner. A large Dominos pizza has 8 slices and a diameter of 13.5 inches. You don't like to eat the crust, so you want to know how much of your pizza slice goes to waste. Determine the arc length of the crust on 1 pizza slice to one decimal place. [2A, 1C] 6. The water level in a lake rises and falls throughout the day. The average depth of the water at low tide is 4 metres, while the average depth at high tide is 8 metres. It takes 6 hours for the water level to rise from low tide to high tide. a) Determine a cosine equation to model the water depth, assuming that at t = 0 hours the water is at low tide. [4A] b) What is the depth of the water 2 hours after low tide? [2A, 1C]