122 7: Fill a cylindrical glass with an inner diameter of 90mm with water, and use it to pour water into a rectangular iron box with a bottom area of 13 1x 1 mm2 and a height of 81mm. What is the height of water in the glass when the iron box is filled with water?

8. The charging standard of an expressway toll station: bus 20 yuan, truck 10 yuan and car 5 yuan. The ratio of the number of three vehicles passing through the toll booth on a certain day is 5: 7: 6, and the charge for * * * is 48,000 yuan. How many vehicles pass through the toll booth on this day?

A transportation company contracted to transport 2000 sets of glass tea sets. According to the transportation contract, the freight for each set is 1.60 yuan. In case of damage, each set will not only get the freight, but also pay 18 yuan. As a result, the shipper got the freight of 3 102 yuan. How many tea sets were damaged during transportation?

123 14, a passenger takes 30 kilograms of luggage to Beijing by plane, and each passenger can take up to 20 kilograms of luggage for free. For the overweight part, buy air tickets 1.5% per kilogram. Now the passenger has bought the baggage fee of 120 yuan and asked for his air ticket.

15 in the rectangular ABCD, put eight rectangles with the same shape and size, and try to find the area of the shaded part.