1. what are some similarities between the dogs pictured? what are some differences? 2. what are some ways you can divide these dogs into groups? 3. how could you improve your dichotomous key? 4. why is it important to classify things?

Sally is making a model of a magnesium atom with an atomic mass number of 24 for her chemistry class. she has foam balls for the protons, neutrons, and electrons. she has added 6 neutrons to her model so far. how many more neutrons does she need to add to complete her neutral atom of magnesium?

In the millikan oil drop experiment they determined that every drop had a charge which was a while number multiple of -1.60x10^-19. if a drop has a total charge of -9.60x10^-19 then how many excess electrons are contained within the drop?

Why is retrograde motion an apparent motion