Which of the following best explains a method by which plants use long-distance signaling to carry out cell communication?

1. Gas hormones are released and travel through the air to reach their target cells.
2. Growth factors are released into extracellular fluid toward target cells via
paracrine signaling.
3. Molecules travel down a concentration gradient to target cells through
plasmodesmata.
4. Neurotransmitters carry chemical signals from dendrites to axons across
synapses.

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 .. .

the dali lama

explanation:

he is quite fat and then we can talk about the details