In mitosis, the end product is two cells: the original parent cell and a new, genetically identical daughter cell. Meiosis is more complex and goes through additional phases to create four genetically different haploid cells which then have the potential to combine and form a new, genetically diverse diploid offspring.
Let's assume the cost for natural gas is $15.00 per 1,000 cubic feet. This means that $15.00 will purchase approximately 1.03 million BTU's of energy. This would be equivalent to 11.26 gallons of propane. At $2.50 per gallon of propane, natural gas would be a more cost effective energy solution. Breaking it down even further, natural gas needs to be more than $28.00 per 1,000 cubic feet for propane to be a more cost effective energy solution (provided the cost for propane is $2.50 per gallon.
Propane is measured by the gallon so propane is priced per gallon. During the 2011-2012 heating season propane prices ranged from $2.74 to $2.88 per gallon, meaning that a 500-gallon tank cost between $1,100 and $1,150 to fill. That propane prices have increased over the last 10 years does not mean that, compared to other sources of energy it is necessarily more expensive.