Explore: Below the helium atom you see the isotope notation for helium-4. Add and subtract protons and neutrons a few times using the arrow buttons. Notice how the isotope notation changes when you do this. A. What does the top number equal?

Arollercoaster car at the top of a hill has potential energy kinetic energy chemical energy light energy

Clyde and marilyn are riding a roller coaster. during which section(s) of the track is their potential energy converted to kinetic energy? a. from point b to point c only b. from point b to point d only c. from point a to point b only d. from point a to point b and from point c to point d

Pegmatites are igneous rocks in which the individual minerals are very large. typically, the minerals are all light-colored quartz, feldspar and muscovite. if you were given a black and white photograph of a pegmatite in a quarry (where the rock has been blasted and broken), what physical properties could you use to identify those three minerals in this hypothetical photo? describe each mineral and the specific diagnostic properties. be specific.