Explain virtual image?

911

---

Explain what is the opaque?

970

---

Explain what is the transparent?

897

---

Tell me why ship doesnt sink sea?

1009

---

Explain what is the ray of light?

924

---

What are the stars?

783

---

What is solar eclipse?

823

---

Explain the planets?

885

---

What is eclipses?

835

---

Explain shape of the earth?

802

---

What is astronomical telescope?

887

---

What is the distance of the earth from the moon and the sun?

805

---

What is lunar eclipse?

835

---

Explain the moon?

819

---

What is equatorial and polar diameter?

795

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