Atom a has an atomic number of 19 and mass number of 40. atom b has an atomic number of 20 and a mass number of 40. which of these is an accurate statement? a) atom a has more protons than atom b. b) atom a has one less proton and one more neutron than atom b. c) atom a has an extra nucleon compared to atom b. d) atom a has one more proton and one more electron than atom b.

clinically, some people often have repeated allergies, eczema and respiratory infections or other parts of the infection, in this case, in addition to some routine tests such as tests for white blood cells, immunoglobulin series, lymphocyte subsets, etc., the five immune immunoglobulin tests are also necessary.

correct answer is option a.

tropopause, stratopause and mesopause have all in common aspect that is point of maximum temperature in its layer of the atmosphere. all layers of atmosphere observe abrupt change in temperature. tropopause is the boundary between troposphere and stratosphere. stratopause is the boundary between stratosphere and mesosphere. mesopause is the boundary between mesosphere and thermosphere. these all boundaries are ranges between altitude of 0 to 80 km.