A radioactive sample has an activity of 450 cpm three half lives after the initial activity was determined. What was the original activity?

If the element whose electric configuration ends in the d sublevel, the element is calssified as? a.inner transition b.noble gases c.representative d. transition

An atom's configuration based on its number of electrons ends at 3p4. another atom has seven more electrons. starting at 3p, what is the remaining configuration? 3p63d34s2 3p43d54s2 3p64s23d3 3p44s23d

Which of the following is true about a carbonated soft drink? . the carbon dioxide is the solvent, and water is the solute.. the water is the solution, and carbon dioxide is the solvent.. the carbon dioxide is the solution, and the water is the solvent.. the water is the solvent, and the carbon dioxide is the solute.. .