1. A girl pulls a 20 kg box with a constant force of 100N neglecting the force of friction, the wagon's acceleration will be
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Which of the following statements is true? a. elements in the last period are radioactive. b. atomic weight is the same as atomic mass. c. elements in the same group have the same number of electron shells. d. atomic number equals the number of neutrons in the nucleus of an atom.

Ais a mountain created from eruptions of lava, ash, rocks, and hot gases.

Will mark brainliest how many electrons can be held in the energy level n = 4?