This is a physics question, not biology, but...
f=1/T where f is frequency and T is the period.
f= 1/(1/3)=3
frequency =3 Hz
Generally people would say that the result are published in journals, and it is true that Journals are often the first opportunity for many people to read about those results.
However, it takes a long time to publish in a journal, and people often present their results to a smaller audience at a conference before the journal is ready.
Https://quizlet.com/17718770/chapter-8-aquatic-biodiversity-flash-cards/
The atomic radius of a chemical element is a measure of the size of its atoms, usually the mean or typical distance from the center of the nucleus to the boundary of the surrounding cloud of electrons.
Answer:
the last one is the right answer
