Answer:
The center of mass for the object is
from the origin
Explanation:
From the question we are told that
The mass of the first object is 
The position of first object with respect to origin 
The mass of the second object is 
The position of second object with respect to origin 
The mass of the third object is 
The position of third object with respect to origin 
The mass of the fourth object is 
The position of fourth object with respect to origin 
Generally the center of mass of the object along the x-axis is zero because all the mass lie on the y axis
Generally the location of the center mass of the object is mathematically represented as

=>
=>
Hydrogen gas is harmless to your feet so since you don’t need protection against it that seems the best answer.
Answer:
magnitude of A − B = 15.81 km
Explanation:
Vector A points in the negative y-direction and has a magnitude of 5 km. Vector B points in the positive x-direction and has a magnitude of 15 km.
According to Cartesian coordinate system, the resultant will start either from tail of A and ends at head of B and vice-versa.
A(0,-5)
B(15,0)
A - B = (-15 i - 5 j )
Magnitude of the vector is given by
|A - B| = 
|A - B| = 
|A - B| = 15.81 km
(3) The frictional force exerted by the floor on the box