I think the answer may be the letter B
The solution for this problem:
Given:
f1 = 0.89 Hz
f2 = 0.63 Hz
Δm = m2 - m1 = 0.603 kg
The frequency of mass-spring oscillation is:
f = (1/2π)√(k/m)
k = m(2πf)²
Then we know that k is constant for both trials, we have:
k = k
m1(2πf1)² = m2(2πf2)²
m1 = m2(f2/f1)²
m1 = (m1+Δm)(f2/f1)²
m1 = Δm/((f1/f2)²-1)
m 1 = 0.603/
(0.89/0.63)^2 – 1
= 0.609 kg or 0.61kg or 610 g
The first: alright, first: you draw the person in the elevator, then draw a red arrow, pointing downwards, beginning from his center of mass. This arrow is representing the gravitational force, Fg.
You can always calculate this right away, if you know his mass, by multiplying his weight in kg by the gravitational constant

let's do it for this case:

the unit of your fg will be in Newton [N]
so, first step solved, Fg is 637.65N
Fg is a field force by the way, and at the same time, the elevator is pushing up on him with 637.65N, so you draw another arrow pointing upwards, ending at the tip of the downwards arrow.
now let's calculate the force of the elevator

so you draw another arrow which is pointing downwards on him, because the elevator is accelating him upwards, making him heavier
the elevator force in this case is a contact force, because it only comes to existence while the two are touching, while Fg is the same everywhere
Answer:
i'm not sure if you are asking as a personal question or a book question so i'm taking it personal.
Explanation:
I was doing a simple task that was handed to me to test my responsibility and I agreed (knowing i am responsible :3). my first thought was "man , this is easy!" but then i started seeing the other kids slaking off and quiting their tasks. I thought that was against the rules, but then i saw my bff doing it too and i thought "this should be ok then!" so i did the same. other kids where still doing it. the teacher came, saw the ones still working and smiled... but when the teacher looked at the ones slaking off omg... his face was like * im gonna kill yall* we took one big gulp and whined. the teacher awarded the ones who completed the task... the others , we had to do our original task but doubled... for 3 weeks!!! it was awful!!!
I WOULD NEVER DO THAT AGAIN!!!
Scientific Notation: 4.580 x 10^-4
Scientific e Notation: 4.580e-4