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:

Answer: b
Explanation:
When heat is released by the system i.e. system loses heat. So, we take it as negative -Q
When the work is done on the system then it is considered as negative work on the system i.e. -W
In this case, the plunger is pulled out, and work is done on the system. So, we take work as negative work -W
Correct option is b
Answer: O horizon
Horizons refers to the distinct layers of soil lying parallel to the earth surface. Horizons develop as a result of soil formation. Soil forms as a result of weathering or rocks and addition of organic matter from the decomposition of plant and animal waste. Each horizon differs from the others on the basis of color, texture, type of particles present in the soil, type of minerals present and amount of organic matter present in the soil.
O horizon is the soil horizon that is located closest to the earth's crust. This horizon consist of undecayed or partially decayed animal and plant waste like shedded leaves, bark, animal skin and feces. As, the matter remains undecomposed, therefore, this horizon consists of low amount of organic matter and it is less fertile for plant growth.
The independent variable is the different amount of repellent each person is given. This is because it does not depend on any variable. The dependent variable is what they are measuring, which would be the number of bites on each volunteer.
I hope this helps! :)