$$ \text { How many } \beta \text {-hydrogen is/are present in 2-methyl-3-phenyl-pentan-1-al? } $$

$$ \text { Which of the following reactions do NOT provide an aldehyde as a product? } $$

$$ \text { What are the major products formed in the following reaction sequence? } $$

$$ \text { What is the major product in the reaction sequence given below? } $$