What is the de Broglie wavelength of a proton with a velocity of 2.5e6
m/s?

The  deBroglie wavelength of a proton with a velocity of 2.5e6  is  λ=1.654*10^24 m2 kg

Explanation:

We have the formula,

λ = h/mv

λ = h/p   (p=mv)  assume mass be 1

λ = 6.62607004 × 10-34 m2 kg / s

/2.5*1.602176634*10^−19*10^6

λ = 6.62607004 × 10-34 m2 kg / s  / 4.005425

*10^-13

λ=1.654*10^24 m2 kg

The  deBroglie wavelength of a proton with a velocity of 2.5e6  is  λ=1.654*10^24 m2 kg

The correct statement is that this represents an open system, and one benefit is that waste does not accumulate in the system.

Explanation:

It is the case of open system, and the system where mass possesses the tendency to move in and out of the system is considered as the open system. The mass getting within the system refers to the water, which is supplemented into the tank, and the parting mass is the water, which is produced.  

The main benefit of utilizing the open system is that the water quality can be maintained so that the fishes remain healthy and do not have to thrive in waste, which is the case in the closed system.