The energy levels within an atom contain- A. Protons
B. Neutrons
C. Isotopes
D. Electrons​

Solve this system of equations using the elimination method?

Facial shaving brushes are either bulb-shaped or fan-shaped. an experiment is to be conducted to determine whether the lather thickness is the same for both types of shaving brushes. in previous studies, it was determined that shaving brush size (small, medium, large) is associated with lather thickness, but shaving brush type (wolf whiskers, maggard razors, frank shaving, and so on) is not associated with lather thickness. how could the experiment best be conducted? by blocking on shaving brush size by blocking on shaving brush type by blocking on shaving brush shape by blocking on lather thickness without blocking

Which of these is the most likely way long-term economic growth takes place? a) increases in interest rates b) increases in overall price level c) increases in labor productivity growth d) increases in labor force participation rate