To find the sum:

Therefore the answer is a^3+12a^2+14a+5.
Hope it helps!
Answer:
D im not sure just my opinion
Given :
The diagonals of rhombus ABCD intersect at E.
∠CAD = 20°.
To Find :
The angle ∠CDA.
Solution :
We know, diagonals of a rhombus bisects each other perpendicularly.
So, ∠DEA = 90°.
In triangle ΔEAD :
∠EAD + ∠AED + ∠EDA = 180°
20° + 90° + ∠EDA = 180°
∠EDA = 70°
Now, we know diagonal of rhombus also bisect the angle between two sides .
So, ∠CDA = 2∠EDA
∠CDA = 2×70°
∠CDA =140°
Therefore, ∠CDA is 140°.
Given:
<span>mantle layer of earth begins about 70 kilometers underneath the surface
</span><span>outer core begins about 2970 kilometers underneath the surface
Since we need to find the position of each layer </span><span>relative to the surface, the surface will serve as the point of origin or 0. Below the surface infers a negative value. So, Mantle layer is -70 km from the surface while outer core is -2970 km under the surface.
Comparing -70 and -2970, -70 has a greater value than -2970. The nearer the number is to the origin or 0, the higher its value.
Comparing the absolute greater value of -70 and -2970, -2970 has a greater absolute value. This is because absolute value is the positive value of the number. Absolute value of -70 is 70 while absolute value of -2970 is 2970. Thus, -2970 has a greater absolute value. </span>