specifications. If your vehicle was originally charged with R12 refrigerant, for example, the oil type specified, 'mineral', will not apply. Additionally, General Motors issues Bulletin # 02-01-39-004B replacing PAG 150 oil with a lower viscocity oil.
The term square in reference to roofing materials refers to 100 square feet of roof area. One square of slate is the amount of slate that it takes to cover 100 square feet of roof area. A 10 foot x 10 foot section of roof would equal one square. So would a 4 foot x 25 foot section. Ditto for a 5 foot x 20 foot.
Because of the slope, a roof generally has a larger square footage than the house it sits on -- a 1,500-square-foot home could have a 2,100-square-foot roof. Building materials are usually sold by the square -- enough to cover 100 square feet -- and it's customary to include an extra 10 percent for waste on a simple roof and 15 percent extra for a more complicated installation.