Driving on the 87 Octane yields 20 mpg so the driver is able to pass 200 miles for $31.00 dollars and the cost per mile will be $0.16. The example above is simplified but shows that even though the entry cost is lower and in the end, the gas will end up costing more.
Weathering of rocks is caused by chemical and mechanical means, and the types of weathering are therefore generally classified as chemical or mechanical (also known as physical).1  Slightly acidic rainwater can react with rock surfaces, dissolving them over time.ockhound. Weathering of rocks is caused by chemical and mechanical means, and the types of weathering are therefore generally classified as chemical or mechanical (also known as physical). 1  Slightly acidic rainwater can react with rock surfaces, dissolving them over time.
weathering is the decay of the rocks of the earth's crust to the exposure to the atmosphere i.e., a process by which the rocks exposed on the surface get broken up into smalle â¦ r particle.there are 2 types of weathering: 1.mechanical weathering 2.chemical weathering.ard rocks, such as granite, weather more slowly than softer rocks, such as limestone. Differential weathering happens when softer rocks weathers away and leaves harder, more resistant rock. behind.