Among the variations on the graphs of the trigonometric functions are shifts--both horizontal and vertical. Such shifts are easily accounted for in the formula of a given function. Take function f, where f (x) = sin(x) .
The running costs vary from gas to electric. The average running cost for an electric water heater is $550. The average running costs of a gas water heater is $400. The difference in usage price per year is $150.
New federal rules for water heaters will mean higher price tag. Now, the cost to buy and install a typical water heater is about $900. New federal regulations for the efficiency of water heaters go into effect April 16 and will lead to higher replacement prices for homeowners but possibly long-term utility bill savings.