Answer:
A combined reaction is when two or more reagents combine __ to form a product
Explanation:
A combination or synthesis reaction, consists of the formation of a substance from the reaction of two or more substances.
Example: A + B -> C
2Na + Cl2 ---> 2NaCl (sodium chloride formation reaction)
Given that,
Mass of the stone, m = 400 g = 0.4 kg
Initial speed, u = 20 m/s
It is climbed to a height of 12 m.
To find,
The work done by the resistance force.
Solution,
Let v is the final speed. It can be calculated by using the conservation of energy.

Work done is equal to the change in kinetic energy. It can be given as follows :

So, the required work done is 32.99 J.
Answer:
Simple awnser Do it yourself I really would help but I have no clue! Sorry
Explanation:
I think it is C. I hope I helped.