Let's start b writing down coordinates of all points:
A(0,0,0)
B(0,5,0)
C(3,5,0)
D(3,0,0)
E(3,0,4)
F(0,0,4)
G(0,5,4)
H(3,5,4)
a.) When we reflect over xz plane x and z coordinates stay same, y coordinate changes to same numerical value but opposite sign. Moving front-back is moving over x-axis, moving left-right is moving over y-axis, moving up-down is moving over z-axis.
A(0,0,0)
Reflecting
A(0,0,0)
B(0,5,0)
Reflecting
B(0,-5,0)
C(3,5,0)
Reflecting
C(3,-5,0)
D(3,0,0)
Reflecting
D(3,0,0)
b.)
A(0,0,0)
Moving
A(-2,-3,1)
B(0,-5,0)
Moving
B(-2,-8,1)
C(3,-5,0)
Moving
C(1,-8,1)
D(3,0,0)
Moving
D(1,-3,1)
We have the given I = 10^-1 and I₀ = 10^-12.
Simply plugging in the values to the equation, we have:
L = 10log(10^-1/10^-12)
L = 110 Db
The answer is D.
(I used a scientific calculator in solving for L).
Answer:
96
Step-by-step explanation:
Using side b as the base, 4 points makes 3 bases (the space in between). With three bases, you can have 3 bases of 1 segment, 2 bases of 2 segments, and 1 base of 3 segments. This equals 6 bases. Each of these can connect to a point on line a. 6x6=36
Using side a as the base, 6 points makes 5 bases. With 5 bases, you can have 5 bases of 1 segment, 4 bases of 2 segments, 3 bases of 3 segments, 2 bases of 4 segments, and 1 base of 5 segments. This equals 15 bases. Each of these can connect to a point on line b. 15x4=60
36+60=96