The periodic table organizes elements bya increasing atomic massb increasing atomic number c decreasing atomic size d different atomic color

B increasing atomic number

Explanation: A periodic table is the table that shows the arrangement of elements in the order of increasing atomic number. In the periodic table, the horizontal rows of elements are called periods while the vertical columns are called groups. All the elements in a given period have the same number of electron shell while all the elements in the same group have the same number of valence electrons (same number of electrons in the outermost shell of their atoms).

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blood enters the heart through two large veins, the inferior and superior vena cava, emptying oxygen-poor blood from the body into the right atrium of the heart. as the ventricle contracts, blood leaves the heart through the pulmonic valve, into the pulmonary artery and to the lungs where it is oxygenated.