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.
1 This will give you the number of square feet that need to be covered.  For example, if your roof measures 10 feet (3.0 m) x 10 feet (3.0 m) and the slope of the roof is 12/12 (45 degrees, which converts to 1.414 in decimal form), you would multiply 10 x 10 x 1.414, to get the total of 141 square feet of roofing.