Car exhaust is an unhealthy result of fossil fuel use. Photo Credit exhaust fulmes image by bilderbox from Fotolia.com. Fossil fuels are among the most commonly used forms of energy in the world. Common fossil fuels include natural gas, coal and petroleum, which is refined to create gasoline.Although fossil fuels are strong sources of energy, their use can pose certain health problems if handled incorrectly.ar exhaust is an unhealthy result of fossil fuel use. Photo Credit exhaust fulmes image by bilderbox from Fotolia.com. Fossil fuels are among the most commonly used forms of energy in the world. Common fossil fuels include natural gas, coal and petroleum, which is refined to create gasoline.
First-Class Mail International is a USPS trademark. Note: The cost of postage will appear on all international shipping labels. Maximum weight for letters is 3.5 ounces. Maximum weight for large envelopes is 4 pounds.
Width restrictions for First-Class envelopes allow up to 0.25 inch, but cannot be less than 0.007 inch thick. Large envelopes shipping First-Class must also be rectangular in shape, and they must not exceed 15 inches in length, 12 inches in height and 0.75 inch in thickness. The maximum weight for First-Class large envelopes is 13 ounces.