Starting making jokes and rapping
The change in velocity is +4 m/s to the right (or -4 m/s to the left).
The object's mass is irrelevant.
Answer:
B)velocity of object decreases
Explanation:
Consider the positive x axis as positive direction
Assume a body moving in negative x-axis direction
It's acceleration also alone negative x-axis direction
So according to our consideration
velocity and acceleration values are negative
That is both are towards negative x direction
But as both velocity and acceleration are in same direction, MAGNITUDE of velocity increases
But as magnitude increases in negative direction, velocity value decreases
But speed value increases(As speed is scalar and velocity is a vector)
I think these two variables are sufficient to completely specify the state.
In an isolated room with air only ,the volume is fixed.Mass ,density and its specific volume can be easily known.
Other thermodynamic properties like entropy, enthalpy etc are also fixed at a given temperature & pressure.