For example, if you had a batch file called stuff.bat and you typed stuff a b c d at the command prompt, the letters a, b, c, and d would be assigned to the variables %1, %2, %3, and %4, respectively.
Fiberglass shingles generally have a longer life expectancy than do asphalt shingles. Properly installed tiled roofs have a normal useful life of 20-30 years or longer, but individual pieces can become cracked or broken or the nails rust out.
Shingles in cooler climates such as the northern United States seem to last longer than those installed in the warmer climates. Studies have shown that the average lifespan for a 20 year shingle in Phoenix, Arizona is around 14 years. In Minneapolis, Minnesota the lifespan was 19.5 years. And in Reading, Pennsylvania, the lifespan was 20.8 years.