Look at the four nucleotides. what do you notice A and T have in common?

What’s the scientific notation for the number 6,840,000,000

What are the first two quantum numbers for the electrons located in subshell 4d? what are the first three quantum numbers for the electrons located in subshell 2s? how many electrons can be held in a sublevel l = 3? how many electrons can be held in the energy level n = 4? how many electrons in an atom can share the quantum numbers n = 4 and l = 3?

State one important difference between a physical change and a chemical change?