How many valence electrons in this atom: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁵ *

What does earth’s rotation on its axis cause? the tides night and day passing of years phases of the moon

Which part of earth’s surface receives the most direct rays from the sun? a) equator b) ocean c) poles d) mountains

This chart lists four kinds of polymers and their sources. what can be known about all four polymers, despite their differences? they come from living things. they share ionic carbon bonds. they are at least 100 monomers long. they are made of repeating subunits.