Explain virtual image?

976

---

Explain what is the opaque?

1027

---

Explain what is the transparent?

972

---

Tell me why ship doesnt sink sea?

1086

---

Explain what is the ray of light?

989

---

What are the stars?

844

---

What is solar eclipse?

879

---

Explain the planets?

937

---

What is eclipses?

893

---

Explain shape of the earth?

844

---

What is astronomical telescope?

936

---

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

862

---

What is lunar eclipse?

884

---

Explain the moon?

905

---

What is equatorial and polar diameter?

860

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