Find the $\text{g.c.d.}$ and $\text{l.c.m.}$ of $72$ and $90$ using the fundamental theorem of arithmetic.

(N/A) Step $1$: Find the prime factorization of $72$ and $90$.
$72 = 2^3 \times 3^2$
$90 = 2^1 \times 3^2 \times 5^1$
Step $2$: Calculate the $\text{g.c.d.}$ (Greatest Common Divisor) by taking the product of the smallest power of each common prime factor.
$\text{g.c.d.}(72, 90) = 2^1 \times 3^2 = 2 \times 9 = 18$
Step $3$: Calculate the $\text{l.c.m.}$ (Least Common Multiple) by taking the product of the highest power of each prime factor involved.
$\text{l.c.m.}(72, 90) = 2^3 \times 3^2 \times 5^1 = 8 \times 9 \times 5 = 360$