Answer:
86°
Step-by-step explanation:
Normally, the building stands at an angle of 90° to the ground (from horizontal)
so,
x = 90° - 4° = 86°
The 30/60/90 right triangle is the biggest cliche in trig. We recall the sides come in ratio 

First x:


Next y:


Choice C
<span>A) 2a + 3b = 12
B) ab = 6 solving for a
B) a = 6 / b then we substitute this into equation A)
</span><span>A) 12 / b + 3b = 12 </span><span>multiplying this by "b"
A) 12 + 3b^2 = 12b
A) 3b^2 -12b +12= 0 dividing by "3"
A) b^2 -4b + 4 = 0
Factoring
(b-2) * (b-2) = 0
b = 2
Since b = 2 then a = 3
</span>NOW, we put these numbers into:
<span>8a^3 +27b^3
</span>
8*3*3*3 + 27*2*2*2
216 + 216
The answer is 512
The "dot product" of two vectors has several different formulas.
Since you are given the x- and y-coordinates of both vectors a and b, we can apply the formula
a dot b = ax*bx + ay*by, where ax=x-component of vector a, by=y comp of vector b, and so on.
So, for the problem at hand, ax * bx + ay * by becomes
3(-2) + (-8)(-6) = -6 + 48 = 42 (answer). Note that the dot product (or "scalar product" is itself a scalar.