Classify the following as fixed or variable costs:

a$.$ Fuel:

b$.$ Interest on company$-$issued bonds:

c$.$ Shipping charges:

d$.$ Payments for raw materials:

$($Click to select$)vv$

e$.$ Real estate taxes:

f$.$ Executive salaries:

g$.$ Insurance premiums:

$($Click to select$)vv$

h$.$ Wage payments:

$($Click to select$)vv$

i$.$ Sales taxes:

j$.$ Rental payments on leased office machinery:

$($Click to select$)vv$