Can you please explain the answers?

For the belief net shown in the figure: . Are variables X and Y conditionally independent, given Z? Explain. 2. Are variables X and W conditionally independent of variables V and Z, given Y? Explain. 3. Are variables X and W conditionally independent of variables V and Z, given U? Explain. 4. Are variables W and V conditionally independent given X? Explain 5. Are variables X and Y independent? Explain. 6. Are variables X and Z independent? Explain