Answer:
The answer to your question is: mass = 38.93 kg
Explanation:
Data
mass = ?
Weight = 382 N
gravity = 9.81 m/s2
Formula
Weight = mass x gravity
mass = weight / gravity
mass = 382 / 9.81 substitution
mass = 38.93 kg result
Answer:

Explanation:
Asúmase que la patinadora experimenta una aceleración constante. La fuerza neta experimentada por la patinadora:
![F_{net} = (50\,kg)\cdot \left[\frac{\left(15\,\frac{m}{s}\right)^{2}-\left(0\,\frac{m}{s}\right)^{2} }{2\cdot (3000\,m)} \right]](https://tex.z-dn.net/?f=F_%7Bnet%7D%20%3D%20%2850%5C%2Ckg%29%5Ccdot%20%5Cleft%5B%5Cfrac%7B%5Cleft%2815%5C%2C%5Cfrac%7Bm%7D%7Bs%7D%5Cright%29%5E%7B2%7D-%5Cleft%280%5C%2C%5Cfrac%7Bm%7D%7Bs%7D%5Cright%29%5E%7B2%7D%20%7D%7B2%5Ccdot%20%283000%5C%2Cm%29%7D%20%5Cright%5D)

Vacum flask has inner layer of glass and outer body of plastic.the glass has a reflective metal layer..when a hot drink is poured into the flask it prevents conduction.tight lid stops the convection.when radiation tries to leave the hot drink the reflective layer of the glass reflects it back so no heat can escape.
We will define the Total mass to calculate the force, so our values are:
Total Mass 
The Weight is,

Through the hook's Law we calculate X.
, where x is the lenght of compression and K the Spring constant.
We don't have a K-Spring, but we can assume a random value (or simply let the equation in function of K)

I assume a value of 
