Answer: B or "diamonds are rare,valuable gems".
Explanation:
since the link does not show very much, I don't know if A is correct or not. D is incorrect because that is an opinion. C is incorrect.
Answer:
Explanation:
Given
For first case
launch angle 
at highest point 
For second case
at highest Point velocity is 
as there is no acceleration in x direction therefore horizontal velocity is same
Answer:
The answer is Mechanical Energy
A. Impulse is simply the product of Force and time.
Therefore,
I = F * t --->
1
where I is impulse, F is force, t is time
However another formula for solving impulse is:
I = m vf – m vi --->
2
where m is mass, vf is final velocity and vi is initial
velocity
Therefore using equation 2 to solve for impulse I:
I = 2000kg (0) – 2000kg (77 m/s)
I = -154,000 kg m/s
B. By conservation of momentum, we also know that Impulse
is conserved. That means that increasing the time by a factor of 3 would still
result in an impuse of -154,000 kg m/s. So,
I = F’ * (3 t) = -154,000 kg m/s
Since t is multiplied by 3, therefore this only means
that Force is decreased by a factor of 3 to keep the impulse constant,
therefore:
(F/3) (3t) = -154,000 kg m/s
Summary of Answers:
A. I = -154,000 kg m/s
B. Force is decreased by factor of 3
Answer: B) Zinc will act as Anode
Explanation:
Standard reduction potential of zinc and nickel are:
![E^0_{[Zn^{2+}/Zn]}= -0.76V](https://tex.z-dn.net/?f=E%5E0_%7B%5BZn%5E%7B2%2B%7D%2FZn%5D%7D%3D%20-0.76V)
![E^0_{[Ni^{2+}/Ni]}=-0.25V](https://tex.z-dn.net/?f=E%5E0_%7B%5BNi%5E%7B2%2B%7D%2FNi%5D%7D%3D-0.25V)
Here Zinc undergoes oxidation by loss of electrons, thus act as anode as it has more negative reduction potential.
Nickel undergoes reduction by gain of electrons and thus act as cathode. as it has less negative reduction potential.
Where both 
are standard reduction potentials.
![E^0=E^0_{[Ni^{2+}/Ni]}- E^0_{[Zn^{2+}/Zn]}](https://tex.z-dn.net/?f=E%5E0%3DE%5E0_%7B%5BNi%5E%7B2%2B%7D%2FNi%5D%7D-%20E%5E0_%7B%5BZn%5E%7B2%2B%7D%2FZn%5D%7D)
As the emf is positive, the reaction is spontaneous and reaction will occur.
Thus Zinc will act as anode.
