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.
Most shingled roofs have a life expectancy of 15-25 years depending on climate, shingle color, weight of the shingle, pitch of the roof, and even how well your attic is ventilated. Most roofing companies will provide you with a free roof evaluation along with an estimate for replacement.