Hello.
The answer is
<span> C. viscosity.
</span>Temperature and silica content determine the viscosity of magma.
The viscosity of amagma<span> is largely controlled by the </span>temperature.
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Have a nice day.</span>
No because the atomic mass is the average of the different isotopes, so there is no isotope with a mass of 35.45. There are no isotopes that have decimal masses, they have to be a whole number.