How can you explain the difference in number of mitochondria in these types of cells?

Organs which need alot of energy to function properly have a greater number of mitochondria

Explanation:

Mitochondria are sites for respiratory enzymes which yield energy for the cells thus skeletal muscles which need alot of energy have more mitochondria than liver and liver due to doing more activities than skin has more mitochondria than the skin.

Skeletal muscle cells have a very high amount of mitochondria as well as liver cells because they need high amounts of energy to carry out their functions, whereas skin cells don't need high amounts of energy to function.

relative dating involves things like higher layers are most recent than rocks lower in the sequence. this can be extended to the known sequence of fossils. rocks containing rabbit fossils are later than those containing dinosaur fossils.  

absolute dating methods mainly use radioactive elements that have known rates of decay and produce recognizable products. for example potassium 40 decays to produce argon. once a rock has solidified the argon is trapped. by measuring the argon and potassium0 you can get an accurate number for the age.  

some other methods are good for archaeological ages. dendrochronology involves recognizing the sequence of tree rings. the orientation of magnetized particles in baked clay can be used to date a fire.

hope this .. .

a chair, a bed, and a toothbrush

explanation: