Explanation:

FIR (Finite Impulse Response) System:
An FIR system is a type of digital filter with a finite impulse response. It is characterized by the fact that its impulse response h(n) is finite in length. The output of an FIR system is obtained by convolving the input signal with the impulse response.

Frequency Response:
The frequency response of a system describes how the system responds to different frequencies. It is obtained by taking the Fourier transform of the impulse response.

Minimum Phase System:
A minimum phase system is a system whose all zeros and poles are inside the unit circle in the z-plane. In other words, all the poles and zeros lie within the region of convergence (ROC) of the system. A minimum phase system is stable and causal.

Maximum Phase System:
A maximum phase system is a system whose all zeros and poles are outside the unit circle in the z-plane. In other words, all the poles and zeros lie outside the region of convergence (ROC) of the system. A maximum phase system is also stable and causal.

Mixed Phase System:
A mixed phase system is a system that has both poles and zeros inside and outside the unit circle in the z-plane. The system can be stable and causal, but it is not minimum phase or maximum phase.

Given FIR System:
The frequency response of the given FIR system is H(z) = 6z^(-1) - z^(-2).

Analysis:
To determine the phase of the system, we need to analyze the locations of the poles and zeros in the z-plane.

Poles and Zeros:
The system has two poles at z = 0 and z = 0, and no zeros.

Unit Circle:
The unit circle in the z-plane represents the region of convergence (ROC) for a system. For minimum phase systems, all poles and zeros should be inside the unit circle.

Analysis of Given FIR System:
In the given FIR system, both poles are at z = 0, which is inside the unit circle. Since all the poles are inside the unit circle, the system is a minimum phase system.

Conclusion:
Based on the analysis, the given FIR system with the frequency response H(z) = 6z^(-1) - z^(-2) is a minimum phase system.