It's methane. While methane is a more potent greenhouse gas than CO2, there is over 200 times more CO2 in the atmosphere. Eg-CO2 levels are 380 ppm (parts per million) while methane levels are 1.75ppm.Hence the amount of warming methane contributes is calculated at 28% of the warming CO2 contributes. Here is a graph of the various forcings that influence climate (methane is CH4, right above CO2).g-CO2 levels are 380 ppm (parts per million) while methane levels are 1.75ppm. Hence the amount of warming methane contributes is calculated at 28% of the warming CO2 contributes. Here is a graph of the various forcings that influence climate (methane is CH4, right above CO2).
A 25 feet distance is required between the two cones to test  parallel parking skills. The cones are assumed to be parked  vehicles in the test.
Common dimensions for straight and angled parking. Dimensions of angle parking spaces. These dimensions are standard for most of the US. They are designed to yield a parking space that is 9'X18' with adequate room for maneuvering in and out of the space.