Reaction between acetone and methylmagnesium chloride followed by hydrolysis will give :

Which of the following statements regarding chemical properties of acetophenone are wrong?
$(1)$ It is reduced to methyl phenyl carbinol by sodium and ethanol
$(2)$ It is oxidised to benzoic acid with acidified $KMnO_4$
$(3)$ It does not undergo electrophilic substitution like nitration at meta position
$(4)$ It does not undergo iodoform reaction with iodine and alkali

$Ph_2CH-C(=O)H \xrightarrow{\text{aqueous acid}} (A) (81\%) + \text{enol} (2\%) + \text{aldehyde} (17\%)$. Product $(A)$ of the above reaction will be:

For the sequence of reactions,$A$ $\xrightarrow[{ether}]{{C_2H_5MgI}} B$ $\xrightarrow{{H_2O/H^{+}}}$ tert-Pentyl alcohol. The compound $A$ in the sequence is

Which of the following compounds will give a positive test with Tollen's reagent?

Which of the following compounds is a hemiacetal?