C. change length and direction
Explanation:
The density of the material in which the light wave is travelling affects the speed of the wave. Different materials have different densities and they effect differently light waves which travel through them. Light waves may change direction at the boundary between two transparent materials, depending on material density. Density also impacts the speed of light. The denser the material, the slower light travels through it. The wavelength also decreases as light travels through the denser medium.
Answer:
sofa
Explanation:
because the sofa is heavy and the amount of friction is high due to the amount of opposite friction is pushing it back
Answer:
Part a)


Part b)

Explanation:
Part a)
Constant speed by which the student will run is given as

now after some time if student is going to overtake the position of bus
so here the final positions will be same
so we have




so it is

So student will run the total distance



Part b)
Speed of bus when student reach the bus is given as



Answer:
The correct question is:
"Find the energy each gains"
The energy gained by a charged particle accelerated through a potential difference is given by

where
q is the charge of the particle
is the potential difference
For a proton,

And since 
The energy gained by the proton is

For an alpha particle,

Therefore, the energy gained is

Finally, for a singly ionized helium nucleus (a helium nucleus that has lost one electron)

So the energy gained is the same as the proton:

Oxygenated blood that has oxygen in them while de-oxygenated blood has carbon dioxide. in which the oxygenated blood carries the oxygen throughout the body since that cells need oxygen to function. called "gas exchange." once the cells got their required oxygen. the carbon dioxide needs somewhere to go, thus having deoxygenated blood. and that carbon dioxide needs to get out of the body