Use signed numbers to solve each problem. EYESIGHT Nearsightedness, the condition in...

Use signed numbers to solve each problem.

EYESIGHT Nearsightedness, the condition in which near objects are clear and far objects are blurry, is measured using negative numbers. Farsightedness, the condition in which far objects are clear and near objects are blurry, is measured using positive numbers. Find the range in the measurements shown in the next column.