Answer: Molarity of a physiological saline solution is 0.15 M
Explanation:
Molarity of a solution is defined as the number of moles of solute dissolved per liter of the solution.

n = moles of solute
=volume of solution in ml
Given : 0.89 g of sodium chloride in 100 ml of solution.
To calculate the moles, we use the equation:

Volume of solution = 100 ml

Molarity of physiological saline solution is 0.15 M
Answer:
2000 years
Explanation:
A radioactive molecule will continuously decay and turn into another molecule. This nature of the radioactive molecule makes them can be used to estimate the age of an object. Half-life is the unit of time needed for radioactive molecules to decay to half of its mass. The formula for the mass remaining will be:

Where
N(t)= number of the molecule remains
N0= number of molecule initially
t= time elapsed
t1/2= half time
We have all variable besides the half time, the calculation will be:




3= 6000/ (t1/2)
t1/2= 6000/3= 2000
The half-life is 2000 years
The answer is A. Every action has an equal and opposite reaction
The answer is selenium which is D