Base ten blocks exercise for learning place value with visual representations of numbers.

To solve the problem, we need to interpret the base ten blocks shown in each row and determine the number they represent. Base ten blocks are a visual tool used to represent numbers in the decimal system, where:

- Large squares (flats) represent 100 units.
- Tall rectangles (longs) represent 10 units.
- Small cubes (units) represent 1 unit.

Let's analyze each row step by step:

---

Row 1:

- Flats (large squares): There are 3 flats. Each flat represents 100 units.
- Total from flats: \( 3 \times 100 = 300 \)
- Longs (tall rectangles): There are 4 longs. Each long represents 10 units.
- Total from longs: \( 4 \times 10 = 40 \)
- Units (small cubes): There are 5 units. Each unit represents 1 unit.
- Total from units: \( 5 \times 1 = 5 \)

Adding these together:
\[
300 + 40 + 5 = 345
\]

So, the number represented in Row 1 is 345.

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Row 2:

- Flats (large squares): There are 2 flats. Each flat represents 100 units.
- Total from flats: \( 2 \times 100 = 200 \)
- Longs (tall rectangles): There are 0 longs.
- Total from longs: \( 0 \times 10 = 0 \)
- Units (small cubes): There are 6 units. Each unit represents 1 unit.
- Total from units: \( 6 \times 1 = 6 \)

Adding these together:
\[
200 + 0 + 6 = 206
\]

So, the number represented in Row 2 is 206.

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Row 3:

- Flats (large squares): There is 1 flat. Each flat represents 100 units.
- Total from flats: \( 1 \times 100 = 100 \)
- Longs (tall rectangles): There are 9 longs. Each long represents 10 units.
- Total from longs: \( 9 \times 10 = 90 \)
- Units (small cubes): There are 7 units. Each unit represents 1 unit.
- Total from units: \( 7 \times 1 = 7 \)

Adding these together:
\[
100 + 90 + 7 = 197
\]

So, the number represented in Row 3 is 197.

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Final Answer:

\[
\boxed{345, 206, 197}
\]