What is the difference between skimming and previewing?

The distinction between a normal and an inferior good is

Oceanside marine company manufactures special metallic materials and decorative fittings for luxury yachts that require highly skilled labor. oceanside uses standard costs to prepare its flexible budget. for the first quarter of the year, direct materials and direct labor standards for one of their popular products were as follows: direct materials: 2 pound per unit; $ 11 per pound direct labor: 2 hours per unit; $ 19 per hour oceanside produced 2 comma 000 units during the quarter. at the end of the quarter, an examination of the direct materials records showed that the company used 7 comma 500 pounds of direct materials and actual total materials costs were $ 98 comma 100. what is the direct materials cost variance? (round any intermediate calculations to the nearest cent, and your final answer to the nearest dollar.)

Experienced problem solvers always consider both the value and units of their answer to a problem. why?