Actual readings for micrometer screw gauges with no zero errors.

To determine the actual readings of the micrometer screw gauges, we need to understand how to read a micrometer. A micrometer typically consists of:

1. Main Scale (Fixed Scale): This is the scale on the sleeve and provides the primary measurement in millimeters.
2. Thimble Scale (Rotating Scale): This is the scale on the thimble and provides the fractional part of the measurement in hundredths or thousandths of a millimeter.

General Reading Procedure:

- Main Scale Reading: Read the number of full millimeters from the main scale.
- Thimble Scale Reading: Count the number of divisions on the thimble scale that align with the reference line on the sleeve. Each division on the thimble scale represents a fraction of a millimeter (e.g., 0.01 mm or 0.001 mm).
- Total Reading: Add the main scale reading and the thimble scale reading.

Let's solve each part step by step:

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a)

- Main Scale Reading: The main scale shows 10 mm.
- Thimble Scale Reading: The thimble scale has 20 divisions, and each division represents 0.01 mm. The alignment is at the 15th division.
- Thimble Scale Reading = \( 15 \times 0.01 = 0.15 \) mm.
- Total Reading:
\[
10 + 0.15 = 10.15 \, \text{mm}
\]

Answer for a): \( \boxed{10.15} \)

---

b)

- Main Scale Reading: The main scale shows 4 mm.
- Thimble Scale Reading: The thimble scale has 50 divisions, and each division represents 0.01 mm. The alignment is at the 45th division.
- Thimble Scale Reading = \( 45 \times 0.01 = 0.45 \) mm.
- Total Reading:
\[
4 + 0.45 = 4.45 \, \text{mm}
\]

Answer for b): \( \boxed{4.45} \)

---

c)

- Main Scale Reading: The main scale shows 9 mm.
- Thimble Scale Reading: The thimble scale has 50 divisions, and each division represents 0.01 mm. The alignment is at the 45th division.
- Thimble Scale Reading = \( 45 \times 0.01 = 0.45 \) mm.
- Total Reading:
\[
9 + 0.45 = 9.45 \, \text{mm}
\]

Answer for c): \( \boxed{9.45} \)

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d)

- Main Scale Reading: The main scale shows 10 mm.
- Thimble Scale Reading: The thimble scale has 50 divisions, and each division represents 0.01 mm. The alignment is at the 0th division.
- Thimble Scale Reading = \( 0 \times 0.01 = 0.00 \) mm.
- Total Reading:
\[
10 + 0.00 = 10.00 \, \text{mm}
\]

Answer for d): \( \boxed{10.00} \)

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e)

- Main Scale Reading: The main scale shows 5 mm.
- Thimble Scale Reading: The thimble scale has 50 divisions, and each division represents 0.01 mm. The alignment is at the 5th division.
- Thimble Scale Reading = \( 5 \times 0.01 = 0.05 \) mm.
- Total Reading:
\[
5 + 0.05 = 5.05 \, \text{mm}
\]

Answer for e): \( \boxed{5.05} \)

---

f)

- Main Scale Reading: The main scale shows 10 mm.
- Thimble Scale Reading: The thimble scale has 50 divisions, and each division represents 0.01 mm. The alignment is at the 5th division.
- Thimble Scale Reading = \( 5 \times 0.01 = 0.05 \) mm.
- Total Reading:
\[
10 + 0.05 = 10.05 \, \text{mm}
\]

Answer for f): \( \boxed{10.05} \)

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Final Answers:

\[
\boxed{10.15, 4.45, 9.45, 10.00, 5.05, 10.05}
\]