What the concept of electronic transition​

Which of the following happens during cell division? (a) energy is created (b) waste is eliminated (c) carbon dioxide is released (d) damaged cells are replaced

How many moles of lead are in 1.50 x 10^12 atoms of lead? could you explain the answer as well and not just give it to me i am refreshing for finals and i need to know how to do it

For the reaction c6h14(g) & longrightarrow; c6h6(g) + 4h2(g), δp(h2)/δt was found to be 2.5 x 10-2 atm/s, where δp(h2) is the change in pressure of hydrogen. determine δp(c6h14)/δt for this reaction at the same time.