Which of the following is a part of the heliocentric model? all objects in space move around earth in perfect circles. all objects in space move around the sun. all objects in space move in parallel tracks. all objects in space are perfect spheres.

The characteristic of two different types of reactions are shown below. reaction a: electrons are gained by the atoms of an element. reaction b: protons are lost by the atom of and element. which statement is true about the atoms of the elements that participate in the two reactions? a: their identity changes in both reaction a and b. b: their identity changes in reaction a but not b. c: their identity changes in reaction b but not a. d: their identity remains the same.

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

What is the area in square meters of 448 g ai foil that has a thickness of 23921 nm? the density is 2.70 g/cm