Explain which way do twin screw props on a boat rotate when propelling the boat forward?

487

---

Explain why does sun appear flat during sunrise and sunset?

502

---

Explain what is the longest lasting synthetic periodic element?

523

---

Tell me what is astrophysics?

518

---

Explain the thermal transformation?

538

---

Tell me what is ion pair energy?

500

---

Explain what is an alloy?

530

---

Explain what is different between secondary electron image and back scattered electron image?

538

---

Explain what is the measure of the force of gravity on an object?

480

---

Explain how do you find your body volume using a tape measure?

564

---

Explain why does a tea kettle sing?

524

---

Explain what is a positron?

540

---

Explain the universal law of universal gravitation?

508

---

Tell me how do you calculate shaft power?

539

---

Explain what is a crest?

516

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