Allergies arise when a foreign material such as pollen, bee venom or pet dander responds to your immune system or a food that in most people does not cause a reaction. Substances known as antibodies are formed by your immune system.
Answer:
C
Explanation:
Because on the moon you are basically weightless and your mass would stay the same
Explanation:
Tc - 99 is technetium 99.
It is a radioactive element that decays spontaneously. It has a half-life of 211,000 years and decays to stable ruthenium.
- On the periodic table, it has an atomic number of 43;
Mass number = 99
Atomic number = number of protons = number of electrons in atom
Number of protons in Tc is 43
electron is 43
Mass number = number of protons + number of neutrons
Number of neutrons = mass number - number of protons = 99-43 = 56
learn more:
Atomic number brainly.com/question/2057656
#learnwithBrainly
