1)Express each number as a product of its prime factors:
(i) 140
$$\begin{array}{r|l}
2 & 140 \\
\hline 2 & 70 \\
\hline 5 & 35 \\
\hline 7 & 7 \\
\hline & 1 \\
\end{array}$$
Hence,
$$\mathbf 140 = 2 \times 2 \times 5 \times 7 = 2^2 \times 5 \times 7$$
(ii) 156
$$\begin{array}{r|l}
2 & 156 \\
\hline 2 & 78 \\
\hline 3 & 39 \\
\hline 13 & 13 \\
\hline & 1 \\
\end{array}$$
Hence,
$$\mathbf 156 = 2 \times 2 \times 3 \times 13 = 2^2 \times 3 \times 13$$
(iii) 3825
$$\begin{array}{r|l}
3 & 3825 \\
\hline 3 & 1275 \\
\hline 5 & 425 \\
\hline 5 & 85 \\
\hline 17 & 17 \\
\hline & 1 \\
\end{array}$$
Hence,
$$\begin{aligned} 3825 &=3 \times 3 \times 5 \times 5 \times 17 \\ & =3^2 \times 5^2 \times 17\end{aligned}$$
(iv) 5005
$$\begin{array}{r|l}
5 & 5005 \\
\hline 7 & 1001 \\
\hline 11 & 143 \\
\hline 13 & 13 \\
\hline & 1 \\
\end{array}$$
Hence,
$$\mathbf 5005 = 5 \times 7 \times 11 \times 13 $$
(v) 7429
$$\begin{array}{r|l}
17 & 7429 \\
\hline 19 & 437 \\
\hline 23 & 23 \\
\hline & 1 \\
\end{array}$$
Hence,
$$\mathbf 7429 = 17 \times 19 \times 23 $$