D.) Tin (Sn) are likely to have a larger atomic radius than silicon....
I would think the last one about the ozone layer
Unicellular organisms...
Contain a single cell in their body
Do not contain membrane bound organelles
Use simple diffusion as a transport mechanism
All cellular processes are carried out by the single cell
Only visible under the microscope
Injury in the cell leads to the death of the organism
Asexually reproduce by binary fission
Sexually reproduce by conjugation
Lifespan is comparatively short
The atomic mass or relative isotopic mass refers to the mass of a single particle, and therefore is tied to a certain specific isotope of an element. The dimensionless standard atomic weight instead refers to the AVERAGE of atomic mass values of a typical naturally-occurring mixture of isotopes for a sample of an element.
You can count it by yourself using formula
m = ({first isotopic distribution%}× {first atomic.mass})+ ({second isotopic distribution%}× {second atomic.mass}) / {100}