85
Natural radioactivity consists of the emission of
- A. α- particles and β-rays
- B. α- particles and X-rays
- C. α- particles, β - rays and y-rays
- D. γ- rays and X-rays
86
The density of 400cm\(^3\) of palm oil was 0.9gcm-3 before frying. If the density of the oil was 0.6gcm-3 after frying, assuming no loss of oil due to spilling, its new volume was?
- A. 1360cm\(^3\)
- B. 600cm\(^3\)
- C. 240cm\(^3\)
- D. 8000m\(^3\)
87
A man walks 1km due east and then 1 km due north His displacement?
- A. √2km N 45°E
- B. 1km N 30°E
- C. 1km N 15°E
- D. √2km N 60°E