<span>Earths crust mineral composition are silicon oxide (SiO2),Magnesium monoxide (MgO),Ferrous oxide(FeO),Calcium monoxide (CaO),Sodium dioxide(Na2O) ,Potassium dioxide(K2O), while the Earths crust are sodium,magnesium,potassium,calcium,iron,aluminum,silicon,and oxygen .Because Earth is based on chemical composition and split up into a crust,mantle,outer core and inner core.</span>
Answer:
Quadratic formula is the tool for solving for an unknown number (usually x)
Step-by-step explanation:
The formula is below
146° + (-39 +x)° = 180°
Subtract 146° on both sides.
(-39 +x)° = 180° - 146°
(-39 +x)° = 34°
(x - 39)° = 34°
Add 39° on both sides
x = 34° + 39°
x = 73°
Your final answer is C) 73.