Business owners are aware that the price of gas is historically high, which has made their vehicle costs soar. The average nationwide price of a gallon of unleaded regular gas on June 17 was $5, compared with $3.08 a year earlier, according to the AAA Gas Prices website. A gallon of diesel averaged $5.78 a gallon, compared with $3.21 a year earlier. Fortunately, the IRS is providing some relief. The tax agency announced an increase in the optional standard mileage rate for the last six months of 2022. Taxpayers may use the optional cents-per-mile rate to calculate the deductible costs of operating a vehicle for business. For the second half of 2022 (July 1–December 31), the standard mileage rate for business travel will be 62.5 cents per...