Answer:
vector of zero magnitude
Explanation:
The displacement is a vector magnitude, therefore, in addition to being a module, it has direction and sense.
In this case it moved 350 m and then returned the same 350 m, so the total displacement is zero.
If we draw the vector, one has a directional direction to the right and the other direction to the left, therefore when adding the two vectors gives a vector of zero magnitude
Most objects move at a constant speed because of friction and acceleration. The constant speed keeps them in place, and keeps a balance.
Answer:
Final volumen first process 
Final Pressure second process 
Explanation:
Using the Ideal Gases Law yoy have for pressure:

where:
P is the pressure, in Pa
n is the nuber of moles of gas
R is the universal gas constant: 8,314 J/mol K
T is the temperature in Kelvin
V is the volumen in cubic meters
Given that the amount of material is constant in the process:

In an isobaric process the pressure is constant so:



Replacing : 

Replacing on the ideal gases formula the pressure at this piont is:

For Temperature the ideal gases formula is:

For the second process you have that
So:




Yes, in general, metalloids are slightly reactive.
They'll vibrate at their characteristic resonant frequency. That depends on the material the object is made of and its shape.