Find $30$ using a one-digit number thrice.

$3^3+3=$ _____

Find $30$ using other one-digit number thrice except $3$.

Iman arranged $8$ number in two columns writing the numbers $1, 2, 3, 4, 5, 7, 8$ and $9$.

Try to get the same sum from the columns replacing only $2$ numbers.

See the following problem. Write it in proper way.

$\begin{array}{cccc}& \mathrm{O}& \mathrm{N}& \mathrm{E}\\ +& \mathrm{T}& \mathrm{W}& \mathrm{O}\\ \mathrm{F}& \mathrm{O}& \mathrm{U}& \mathrm{R}\end{array}$