The power in C is correct. it is x / 37 So B,C and D all have the correct power. Now you must turn to the base. You are talking about a half life so what is raised to the the correct power must be 1/2
That eliminates D and C both.
A is gone because it has the wrong power.
B <<<< the first part of the question's answer.
Now we will answer the 6 days part.
y = 477 * (1/2) ^(x / 37)
x = 6
y = 477 * (1/2)^ (6/37)
y = 477 * (1/2)^ (0.162 [repeating] )
y = 477 * 0.8397
y = 426.2876 which is confirmed by the answer given. <<<< second answer.
0.0045 is the answer so if wrong
1. Domain.
We have

in the denominator, so:
![x^2-2x-3\neq0\\\\(x^2-2x+1)-4\neq0\\\\(x-1)^2-4\neq0\\\\(x-1)^2-2^2\neq0\qquad\qquad[\text{use }a^2-b^2=(a-b)(a+b)]\\\\(x-1-2)(x-1+2)\neq0\\\\ (x-3)(x+1)\neq0\\\\\boxed{x\neq3\qquad\wedge\qquad x\neq-1}](https://tex.z-dn.net/?f=x%5E2-2x-3%5Cneq0%5C%5C%5C%5C%28x%5E2-2x%2B1%29-4%5Cneq0%5C%5C%5C%5C%28x-1%29%5E2-4%5Cneq0%5C%5C%5C%5C%28x-1%29%5E2-2%5E2%5Cneq0%5Cqquad%5Cqquad%5B%5Ctext%7Buse%20%7Da%5E2-b%5E2%3D%28a-b%29%28a%2Bb%29%5D%5C%5C%5C%5C%28x-1-2%29%28x-1%2B2%29%5Cneq0%5C%5C%5C%5C%0A%28x-3%29%28x%2B1%29%5Cneq0%5C%5C%5C%5C%5Cboxed%7Bx%5Cneq3%5Cqquad%5Cwedge%5Cqquad%20x%5Cneq-1%7D)
So there is a hole or an asymptote at x = 3 and x = -1 and we know, that answer B) is wrong.
2. Asymptotes:

We have only one asymptote at x = -1 (and hole at x = 3), thus the correct answer is A)
<span>2153.28 hundreds to be exact or, 2153.</span>