From 1998 to 2004, the price of gasoline fluctuated between $1 and $2 USD per U.S.
More recently, the U.S.experienced an upswing in gas prices through 2011, and by 1 March 2012, the national average was $3.74 per gallon. In the United States, most consumer goods bear pre-tax prices, but gasoline prices are posted with taxes included.
Taxes are added by federal, state, and local governments.
As of 2009, the federal tax is 18.4? per gallon for gasoline and 24.4? per gallon for diesel (excluding red diesel).Among states, the highest gasoline tax rates, including the federal taxes as of 2005, are New York (62.9?/gal), Hawaii (60.1?/gal), and California (60?/gal). However, many states' taxes are a percentage and thus vary in amount depending on the cost of the gasoline. About 9% of all gasoline sold in the US in May 2009 was premium grade, according to the Energy Information Administration. Consumer Reports magazine says, "If (your owner?s manual) says to use regular fuel, do so?there?s no advantage to a higher grade." The Associated Press said premium gas?which is a higher octane and costs more per gallon than regular unleaded?should be used only if the manufacturer says it is "required".
Cars with turbocharged engines and high compression ratios often specify premium gas because higher octane fuels reduce the incidence of "knock", or fuel pre-detonation.The price of gas varies during the summer and winter months.Źródło: https://en.wikipedia.org/wiki/Gasoline
In the crankcase of a vehicle engine, motor oil lubricates rotating or sliding surfaces between the crankshaft journal bearings (main bearings and big-end bearings), and rods connecting the pistons to the crankshaft.The oil collects in an oil pan, or sump, at the bottom of the crankcase. In some small engines such as lawn mower engines, dippers on the bottoms of connecting rods dip into the oil at the bottom and splash it around the crankcase as needed to lubricate parts inside.
In modern vehicle engines, the oil pump takes oil from the oil pan and sends it through the oil filter into oil galleries, from which the oil lubricates the main bearings holding the crankshaft up at the main journals and camshaft bearings operating the valves.
This oil film also serves as a seal between the piston rings and cylinder walls to separate the combustion chamber in the cylinder head from the crankcase.The oil then drips back down into the oil pan.45 Motor oil may also serve as a cooling agent. In some constructions oil is sprayed through a nozzle inside the crankcase onto the piston to provide cooling of specific parts that undergo high temperature strain. On the other hand, the thermal capacity of the oil pool has to be filled, i.e.
the oil has to reach its designed temperature range before it can protect the engine under high load.
This typically takes longer than heating the main cooling agent ? water or mixtures thereof ? up to its operating temperature.In order to inform the driver about the oil temperature, some older and most high performance or racing engines feature an oil thermometer. Due to its high viscosity, motor oil is not always the preferred oil for certain applications.
Some applications make use of lighter products such as WD-40, when a lighter oil is desired, or honing oil if the desired viscosity needs to be mid-range.6Źródło: https://en.wikipedia.org/wiki/Motor_oil
And there is nothing surprising in this - after all, the car provides independence and is extremely convenient means of transport.Each vehicle requires service from time to time, or repair certain faults or replacement of wearing parts in everyday life. This makes the mechanics willing to assume workshops.