Answer : The 
must be administered.
Solution :
As we are given that a vial containing radioactive selenium-75 has an activity of 
.
As, 3.0 mCi radioactive selenium-75 present in 1 ml
So, 2.6 mCi radioactive selenium-75 present in 
Conversion :
Therefore, the must be administered.
C is the answer.
It says on the third picture that Bohr refined Rutherford's model by giving distinct orbits for the electrons with distinct radii.
Answer:
68133080.02 g
Explanation:
I believe that the question is to find the mass of air in the room and not the molar mass of air since the molar mass of air was already given in the question as 28.97 g/mol.
Now, if 1 mole of a gas occupies 22.4 L
x moles of air occupies 52,681,428.8 Liters
x = 1 * 52,681,428.8 /22.4
x = 2351849.5 moles of air
Now, number of moles = mass/ molar mass
but molar mass = 28.97 g/mol
2351849.5 = mass/28.97
mass = 2351849.5 * 28.97
mass = 68133080.02 g
An isotope is when an element has the same number of protons and different number of neutrons. That is why the atomic mass changes.
The boundaries of time zones correspond<span> roughly to lines of longitude
</span>This is why:
<span>The time in each successive time zone is one hour different from the times in neighboring time zones. To establish time zones,
Earth's rotation rate of 360 degrees of longitude per day was divided
by 24 hours. The result shows that Earth turns 15 degrees of longitude
per hour.
Hopefully I helped ^.^ Mark Brainly if possible~
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