Answer sheet for a multiple-choice exam with structured question sections and response grids.

The image you provided contains a series of number line problems. Each problem involves identifying the missing numbers on a number line and determining the "UNIT" (the interval or step size) between consecutive marks on the number line.

Step-by-Step Solution:

#### Problem 1:
- Number Line: Starts at 0, ends at 900, with 10 evenly spaced marks.
- Given Marks: 0, 300, 600, 900.
- Missing Marks: The number line is divided into 10 equal parts. To find the unit, divide the total range (900 - 0) by the number of intervals (10 - 1 = 9):
\[
\text{Unit} = \frac{900}{9} = 100
\]
- Missing Numbers: Starting from 0 and adding the unit (100) successively:
\[
0, 100, 200, 300, 400, 500, 600, 700, 800, 900
\]
- Answer:
- Missing Numbers: 100, 200, 400, 500, 700, 800
- Unit: 100

#### Problem 2:
- Number Line: Starts at 0, ends at 900, with 10 evenly spaced marks.
- Given Marks: 0, 200, 400, 600, 800.
- Missing Marks: The number line is divided into 10 equal parts. To find the unit, divide the total range (900 - 0) by the number of intervals (10 - 1 = 9):
\[
\text{Unit} = \frac{900}{9} = 100
\]
- Missing Numbers: Starting from 0 and adding the unit (100) successively:
\[
0, 100, 200, 300, 400, 500, 600, 700, 800, 900
\]
- Answer:
- Missing Numbers: 100, 300, 500, 700, 900
- Unit: 100

#### Problem 3:
- Number Line: Starts at 0, ends at 900, with 10 evenly spaced marks.
- Given Marks: 0, 300, 600, 900.
- Missing Marks: The number line is divided into 10 equal parts. To find the unit, divide the total range (900 - 0) by the number of intervals (10 - 1 = 9):
\[
\text{Unit} = \frac{900}{9} = 100
\]
- Missing Numbers: Starting from 0 and adding the unit (100) successively:
\[
0, 100, 200, 300, 400, 500, 600, 700, 800, 900
\]
- Answer:
- Missing Numbers: 100, 200, 400, 500, 700, 800
- Unit: 100

#### Problem 4:
- Number Line: Starts at 0, ends at 900, with 10 evenly spaced marks.
- Given Marks: 0, 200, 400, 600, 800.
- Missing Marks: The number line is divided into 10 equal parts. To find the unit, divide the total range (900 - 0) by the number of intervals (10 - 1 = 9):
\[
\text{Unit} = \frac{900}{9} = 100
\]
- Missing Numbers: Starting from 0 and adding the unit (100) successively:
\[
0, 100, 200, 300, 400, 500, 600, 700, 800, 900
\]
- Answer:
- Missing Numbers: 100, 300, 500, 700, 900
- Unit: 100

#### Problem 5:
- Number Line: Starts at 0, ends at 900, with 10 evenly spaced marks.
- Given Marks: 0, 300, 600, 900.
- Missing Marks: The number line is divided into 10 equal parts. To find the unit, divide the total range (900 - 0) by the number of intervals (10 - 1 = 9):
\[
\text{Unit} = \frac{900}{9} = 100
\]
- Missing Numbers: Starting from 0 and adding the unit (100) successively:
\[
0, 100, 200, 300, 400, 500, 600, 700, 800, 900
\]
- Answer:
- Missing Numbers: 100, 200, 400, 500, 700, 800
- Unit: 100

#### Problem 6:
- Number Line: Starts at 0, ends at 900, with 10 evenly spaced marks.
- Given Marks: 0, 200, 400, 600, 800.
- Missing Marks: The number line is divided into 10 equal parts. To find the unit, divide the total range (900 - 0) by the number of intervals (10 - 1 = 9):
\[
\text{Unit} = \frac{900}{9} = 100
\]
- Missing Numbers: Starting from 0 and adding the unit (100) successively:
\[
0, 100, 200, 300, 400, 500, 600, 700, 800, 900
\]
- Answer:
- Missing Numbers: 100, 300, 500, 700, 900
- Unit: 100

Final Answers:

1. Missing Numbers: 100, 200, 400, 500, 700, 800; Unit: 100
2. Missing Numbers: 100, 300, 500, 700, 900; Unit: 100
3. Missing Numbers: 100, 200, 400, 500, 700, 800; Unit: 100
4. Missing Numbers: 100, 300, 500, 700, 900; Unit: 100
5. Missing Numbers: 100, 200, 400, 500, 700, 800; Unit: 100
6. Missing Numbers: 100, 300, 500, 700, 900; Unit: 100

\boxed{
\begin{array}{ll}
\text{Problem 1:} & \text{Missing Numbers: 100, 200, 400, 500, 700, 800; Unit: 100} \\
\text{Problem 2:} & \text{Missing Numbers: 100, 300, 500, 700, 900; Unit: 100} \\
\text{Problem 3:} & \text{Missing Numbers: 100, 200, 400, 500, 700, 800; Unit: 100} \\
\text{Problem 4:} & \text{Missing Numbers: 100, 300, 500, 700, 900; Unit: 100} \\
\text{Problem 5:} & \text{Missing Numbers: 100, 200, 400, 500, 700, 800; Unit: 100} \\
\text{Problem 6:} & \text{Missing Numbers: 100, 300, 500, 700, 900; Unit: 100} \\
\end{array}
}