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The diagram shows a portion of the periodic table. Elements that were unknown during Mendeleev's time have been removed. Using Mendeleev's rules for arranging elements, which box would contain the metal gallium, which has an atomic number of 31 and an atomic mass of 70? *

The of a machine determines its "usefulness." a. input force b. output force c. mechanical advantage

Arunner is training for an upcoming marathon by running around a 100-m-diameter circular track at constant speed. let a coordinate system have its origin at the center of the circle with the x-axis pointing east and the y-axis north. the runner starts at (x, y) = (50 m, 0 m) and runs 2.5 times around the track in a clockwise direction.

Wave functions describe orbitals in a hydrogen atom. each function is characterized by 3 quantum numbers: n, l, and ml. if the value of n = 2: the quantum number l can have values from to . the total number of orbitals possible at the n = 2 energy level is .