Kinetic Energy = 1/2xmassx(velocity)^2
Input values;
K.E=1/2x7kgx(4m/s)^2
K.E.=56J
The relationship between mass m, volume V and density d is:

The silver has density

, and the mass of the piece of silver is

. Therefore we can calculate its volume using the previous formula:
<h3>Answer</h3>
C
The object is at rest or is traveling at constant velocity.
<h3>Explanation</h3>
Acceleration is rate of change of velocity and velocity is a vector quantity which means that it is speed with direction.
If acceleration is zero it means that velocity is constant.
Constant velocity may include zero velocity or "at rest"
and
Speed is zero or speed is constant and no change in direction
Answer:
allow the downward movement of the concentration gradient by passive transport
Explanation:
Passive transport is a process of substance transport, which is carried out spontaneously, without energy expenditure and in favor of the concentration gradient, that is, from a medium where the molecules are more concentrated towards a medium where their concentration is lower.
Three types of passive transport are distinguished: osmosis, simple diffusion and facilitated diffusion
<u>Simple diffusion</u>
It is the passage, through the plasma membrane, of small molecules without charge soluble in the lipid bilayer, such as some gases (oxygen and carbon dioxide). For a molecule to diffuse through the membrane it is necessary that there is a difference in concentration between the external and the internal environment.
<u>Diffusion facilitated
</u>
There are molecules such as amino acids, glucose and small ions that, due to their chemical and size characteristics, cannot diffuse through the lipid bilayer and require transport proteins for diffusion.
The transport proteins are immersed in the plasma membrane and can be of two types: protein channels, formed by proteins that generate a channel in the membrane, and permeases, which are proteins that, when joined to the molecule to be transported, change their shape by carrying them into the cell.