D.
All follow an elliptical path that has two foci, rather than a circular path.
Kepler found paths are elliptical, not circular
Answer:
The Arsenic has three electron-containing orbitals. The orbitals s, p and d.
Explanation:
Arsenic is an element with an atomic number equal of 33, it means that it has 33 electrons in its orbitals in the following way:








Therefore, the Arsenic has three electron-containing orbitals (s, p d).
The answer is C. in sort of a way. You can't technically see black matter. However, it is holding the galaxies together.
Climatology is a subspecialty of Meterology.
Answer:
The speed of the electron is 1.371 x 10⁶ m/s.
Explanation:
Given;
wavelength of the ultraviolet light beam, λ = 130 nm = 130 x 10⁻⁹ m
the work function of the molybdenum surface, W₀ = 4.2 eV = 6.728 x 10⁻¹⁹ J
The energy of the incident light is given by;
E = hf
where;
h is Planck's constant = 6.626 x 10⁻³⁴ J/s
f = c / λ

Photo electric effect equation is given by;
E = W₀ + K.E
Where;
K.E is the kinetic energy of the emitted electron
K.E = E - W₀
K.E = 15.291 x 10⁻¹⁹ J - 6.728 x 10⁻¹⁹ J
K.E = 8.563 x 10⁻¹⁹ J
Kinetic energy of the emitted electron is given by;
K.E = ¹/₂mv²
where;
m is mass of the electron = 9.11 x 10⁻³¹ kg
v is the speed of the electron

Therefore, the speed of the electron is 1.371 x 10⁶ m/s.