I would say a. lithium but i am not sure.
As your question is vague, I am assuming that you are talking Alpha, Beta and Gamma radiation. Out of these three radiation, Gamma radiation is the smallest in size compared to Alpha or Beta, but it has the highest energy levels. Gamma radiation is also known as photons. In other words, photons are light particles.
8 looks right to me but not 100%
In order to determine the mass of lead, Pb, that would have an identical volume as 20.1 g of mercury, Hg, we first get the equivalent volume of 20.1 g of mercury. This can be done by using the given density of mercury which is equal to 13.6 g/cm^3. This is shown in the following equation:
20.1 g Hg/ 13.6g/cm^3 = 1.4779 cm^3 of Hg
Consequently, we use this obtained volume which is the target volume for lead. Again, we make use of the density of the substance, in this case, lead has a density of 11.4 g/cm^3. The resulting equation is then:
11.4 g/cm^3 x 1.4779 cm^3 = 16.8485 g of Pb
Thus, the amount of lead that has an identical volume as 20.1 g of mercury is 16.8485 g Pb.
Divide by 1000
145÷1000=0.145
Hope this will be helpful.
