Chelsa Manufacturing Co$.\text{'}$s static budget at $5,000$ units of production includes $$40,000$ for direct labor and $$5,000$ for variable electric power. Total fixed costs are $$23,000.$ At $8,000$ units of production, a flexible budget would show

a$.$ variable costs of $$72,000$ and $$23,000$ of fixed costs

b$.$ variable costs of $$64,000$ and $$23,000$ of fixed costs

c$.$ variable and fixed costs totaling $$107,000$

d$.$ variable costs of $$64,000$ and $$28,000$ of fixed costs