The half-life of Th-232 is 1.405 × 10¹⁰ years
Time elapsed = 2.8 x 10⁹ years
Equation of radioactive decay:
A = A₀ = (1/2)^ t/t₁/₂
Thus, the percentage of thorium-232 in the rock that was dated at 2.8 billions year = 87.1%
2 liters may be 1.5 to 1.9 rounded up to 2 or 2.1 or 2.4 rounded down to 2.
2 - 1.5 = 0.5
percent error = (absolute error / quantity) * 100
percent error = 0.5/2 * 100% = 0.25 * 100% = 25%
Choice C. 25%.
Specialized proteins which function as catalysts for organic reactions are enzymes.
The reaction is given by

Barium goes underneath beta decay to form Ceaseum
- Cs is very mellable element
- It can melt on your hand
Look at the liter man it’s a great way to learn how much every liquid measurement is