As more information was gathered about the structure of the atom, atomic models changed over time. Maxwell Planck discovered that the energies of electrons were quantized. In other words, electrons could only exist in certain energy levels. Which model best shows
this concept?

Select the correct answer from each drop-down menu.describe what happens to a carbon-11 atom when it undergoes positron emission.the decay of a carbon-11 atom _1_, and this causes it to emit _2_.options for 1: > changes a neutron into a proton> changes a proton into a neutron> is hit with a neutron> reconfigures its protons and neutronsoptions for 2: > a negatively charged electron-sized particle> a positively charged election-sized particle> two atoms and several neutrons> two neutrons and two protons

Read "who built the pyramids? ”. leave this link open while you answer the questions throughout the assignment. give at least two reasons why some people claim the pyramids of giza were constructed by aliens.

Ahelium balloon contains 16.9 l of helium at stp. how many atoms of helium are in the balloon