# Querying with a Single Condition
import pandas as pd

df = pd.DataFrame({
    'A': [1, 2, 3, 4],
    'B': ['x', 'y', 'z', 'w']
})
result = df.query('A > 2')
print(result)

# Using Boolean Indexing
import pandas as pd

df = pd.DataFrame({
    'A': [1, 2, 3, 4],
    'B': ['x', 'y', 'z', 'w']
})
result = df[df['A'] > 2]
print(result)

# Querying with Multiple Conditions
import pandas as pd

df = pd.DataFrame({
    'A': [1, 2, 3, 4],
    'B': ['x', 'y', 'z', 'w']
})
result = df.query('A > 2 & B == "z"')
print(result)

# Using Boolean Indexing
import pandas as pd

df = pd.DataFrame({
    'A': [1, 2, 3, 4],
    'B': ['x', 'y', 'z', 'w']
})
result = df[(df['A'] > 2) & (df['B'] == 'z')]
print(result)