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.
Weight restrictions for domestic are 70 lb s. International are 4 lbs for the Flat Rate Envelopes, Small Flat Rate Box, DVD Box, and Large Video Box; 20 lbs for the Medium a nd Large Flat Rate Boxes. Mail Express International Flat Rate Envelopes have a maximum weight of 4 lbs.