Find the Unit Value: Identifying 3 in 32,145

The solution to this problem involves determining the place value of the digit '3' in the number 32,145. Each digit in a number contributes a value depending on its place. The place values are, from right to left, units (ones), tens, hundreds, thousands, ten-thousands, etc.

In 32,145, starting from the rightmost digit:

• 5 is in the units place.
• 4 is in the tens place.
• 1 is in the hundreds place.
• 2 is in the thousands place.
• 3 is in the ten-thousands place.

The digit '3' is positioned in the ten-thousands place. This means it contributes $30,000$ to the total value of the number. This is calculated as $3 \times 10,000$.

The correct choice from the given options, which matches our calculated unit value for the digit '3', is:

• Choice 2: $30,000$

Therefore, the unit value of the digit '3' in the number 32,145 is $30,000$.