Students decide to remove the litter from an abandoned park and plant trees. Which of the following observations provides the best evidence that the action of the students has had a positive effect on the health of the park ecosystem?

The agent of mechanical weathering in which rock is worn away by the grinding action of other rock particles is call

1)each group 16 element has how many valence electrons? ( )4 ( )6 ( )8 ( )16 2)how many dots appear in the dot structure for calcium ion, ca2+? ( )zero ( )one ( )two ( )eight 3) which of the following atoms forms a cation to obtain an octet of outer shell electrons? ( )magnesium ( )oxygen ( )fluorine ( )helium 4) an al3+ ion contains 13 protons and 10 electrons. ( )true ( )false 5) valence and non-valence electrons are represented in lewis dot structures. ( )true ( )false

George is a dalmatian puppy. describe what happens to light that allows you to see george’s black and white coat.