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.
1 Parking spaces in a layout other than parallel shall not be less than nine (9) feet in width and nineteen (19) feet in length.  Parking spaces in a parallel layout shall not be less than twenty four (24) feet in length, measured parallel to the travel lane, and have a width not less than nine (9) feet, perpendicular to the travel lane.