Answer:
B. 26amu
Explanation:
The nucleus of an atom in an element contains protons, electrons and neutrons. The proton number equals the electron number in a neutral atom. The proton number is also called the atomic number, denoted by Z.
The mass number also called Atomic mass unit (amu) in this case, of an element is the sum of the proton number and the neutron number in the atom of that element. The mass number is denoted by A.
Hence, A = Z + N
Where A = Mass number
Z = Proton (atomic number)
N = Neutron number
In this question, N is 11 while Z is 15
Hence, the mass number of the element in the question, in AMU, is 15 + 11 = 26amu.
I do beleive that the answer is c
Answer:
There are three main classes of parasites that can cause disease in humans: protozoa, helminths, and ectoparasites. Protozoa are microscopic, one-celled organisms that can be free-living or parasitic in nature.
Explanation:
Edwin Hubble used the Doppler effect to determine that the universe is expanding. After years of scientific research and observation of different celestial bodies through a telescope, Hubble found that the light from distant galaxies was shifted towards the red end of the spectrum. This red shift indicates that stars are moving away from us and from each other. This phenomenon is called the 'expansion of the universe', also known as the big band theory.