Facts about Inventions The table lists $10$ inventions, together

with other pertinent data.

Let $U=$ the set of all $10$ inventions,

$A=$ the set of items invented in the United States,

and $T=$ the set of items invented in the twentieth

century.

List the elements of each set.

$AT$

$(AT{)}^{\text{'}}$

$T^{\text{'}}-A^{\text{'}}$

Solve each problem.

The numerals in the Venn diagram indicate the number

of elements in each particular region. Determine the

number of elements in each set.