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  1. It was formed approximately 4.5 billion years ago, is a terrestrial planet and is the second smallest of the Solar System 's planets with a diameter of 6,779 km (4,212 mi). A Martian solar day ( sol) is 24.5 hours and a Martian solar year is 1.88 Earth years (687 Earth days). Mars has two small and irregular natural satellites: Phobos and Deimos.

  2. en.wikipedia.org › wiki › PubMedPubMed - Wikipedia

    PubMed is a free database including primarily the MEDLINE database of references and abstracts on life sciences and biomedical topics. The United States National Library of Medicine (NLM) at the National Institutes of Health maintains the database as part of the Entrez system of information retrieval. [1]

  3. The periodic table, also known as the periodic table of the elements, is an ordered arrangement of the chemical elements into rows ("periods") and columns ("groups").It is an icon of chemistry and is widely used in physics and other sciences. It is a depiction of the periodic law, which states that when the elements are arranged in order of their atomic numbers an approximate recurrence of ...

  4. 129,000–226,000. On 6 and 9 August 1945, the United States detonated two atomic bombs over the Japanese cities of Hiroshima and Nagasaki. The bombings killed between 129,000 and 226,000 people, most of whom were civilians, and remain the only use of nuclear weapons in an armed conflict. Japan surrendered to the Allies on 15 August, six days ...

  5. This is a list of roots, suffixes, and prefixes used in medical terminology, their meanings, and their etymologies.Most of them are combining forms in Neo-Latin and hence international scientific vocabulary.There are a few general rules about how they combine. First, prefixes and suffixes, most of which are derived from ancient Greek or classical Latin, have a droppable vowel, usually -o-.

  6. en.wikipedia.org › wiki › WikipediaWikipedia - Wikipedia

    Wikipedia[note 3] is a free content online encyclopedia written and maintained by a community of volunteers, known as Wikipedians, through open collaboration and the use of the wiki-based editing system MediaWiki. Wikipedia is the largest and most-read reference work in history.[3][4] It is consistently ranked as one of the ten most popular ...

  7. en.wikipedia.org › wiki › TaiwanTaiwan - Wikipedia

    Taiwan,[II][k] officially the Republic of China (ROC),[I][l] is a country[27] in East Asia.[o] It is located at the junction of the East and South China Seas in the northwestern Pacific Ocean, with the People's Republic of China (PRC) to the northwest, Japan to the northeast, and the Philippines to the south. The territories controlled by the ...