Answer:
A) Its density will decrease
Explanation:
When an object is heated, its volume increases. This is due to the fact that the particles in the medium vibrate more (if it is a solid) or they move more (if it is a liquid or a gas), therefore they tend to occupy a larger space.
At the same time, the mass of the object does not change, because the mass just represents the amount of matter contained in the object, so it does not increase/decrease at different temperatures.
The density of an object is defined as the ratio between the mass (m) and the volume (V):

We said that the mass remains unchanged while the volume increases: since the density is inversely proportional to the volume, this means that the density decreases.
For the answer to this question,
Thalia must consider the weight of the object and the mass of the sculpture. Weight and mass are different things. She should also consider the time on how long it will take to move it and where she'll move it.
Answer:
0.15
Explanation:
Assuming the rope is horizontal, sum the forces in the y direction:
∑F = ma
N − mg = 0
N = mg
Sum the forces in the x direction:
∑F = ma
F − Nμ = ma
Substitute:
F − mgμ = ma
mgμ = F − ma
μ = (F − ma) / (mg)
Plug in values:
μ = (8.0 N − 2.0 kg × 2.5 m/s²) / (2.0 kg × 9.8 m/s²)
μ = 0.15
Answer:
The detailed calculations are shown below;
Explanation:
a)The maximum acceleration of the particle:
It is seen that the maximum change in velocity is at the time between 8s to 10s.
Maximum acceleration: 
= 
= 10 m/
b) The deceleration of the particle
The velocity of particle is decreased after 10s so,
deceleration = - 
= - 6.67 m/
c)The total distance traveled by the particle = Area under the curve
=
* 4*20 + 4*20 +
* 2*20+ 2*20+
* 40*16
= 290 m
d)The average velocity of the particle = 
= 
= 18.12 m/s