Questions (120)
Q1CDS2018
Which one of the following elements is used as a timekeeper in atomic clocks?
- A Potassium
- B Caesium ✓
- C Calcium
- D Magnesium
✓ Correct answer: (B)
Science & Technology › Physics & Chemistry
Q2CDS2018
Which one of the following elements is involved in the control of water content of the blood?
- A Potassium ✓
- B Lithium
- C Rubidium
- D Caesium
✓ Correct answer: (A)
Science & Technology › Biology & Health
Q3CDS2018
Which one of the following gases dissolves in water to give acidic solution?
- A Carbon dioxide ✓
- B Oxygen
- C Nitrogen
- D Hydrogen
✓ Correct answer: (A)
Science & Technology › Physics & Chemistry
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