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.
The Priority Mail InternaÂ­tional Flat-Rate Envelope may not be insured. Q. Is it true that Priority Mail Flat-Rate Boxes and Priority Mail Flat-Rate Envelops are now available for internaÂ­tional use? A. Yes. The flat-rate box has a 20-pound weight limit for allowable contents, and the flat-rate envelope has a 4-pound weight limit. Note: Use former domestic packaging until supplies are depleted. Although the packaging says âFor Domestic Use Only,â it can be used for both domestic and international shipments.