Which kind of fission is favoured by sunlight?

The order of decreasing reactivity in electrophilic addition of the following compounds is
$(I) \, Ph-CH=CH-COOH$
$(II) \, p-NO_2-C_6H_4-CH=CH-COOH$
$(III) \, p-MeO-C_6H_4-CH=CH-COOH$
$(IV) \, p-Cl-C_6H_4-CH=CH-COOH$

Different possible thermal decomposition pathways for peroxyesters are shown below. Match each pathway from List-$I$ with an appropriate structure from List-$II$ and select the correct answer using the code given below the lists.
List-$I$:
$P$. Pathway $P$
$Q$. Pathway $Q$
$R$. Pathway $R$
$S$. Pathway $S$
List-$II$:
$1$. $C_6H_5CH_2CO_3CH_3$
$2$. $C_6H_5CO_3CH_3$
$3$. $C_6H_5CH_2CO_3C(CH_3)_2CH_2C_6H_5$
$4$. $C_6H_5CO_3C(CH_3)_2C_6H_5$
Codes:
$P \quad Q \quad R \quad S$
$A. 1 \quad 3 \quad 4 \quad 2$
$B. 2 \quad 4 \quad 3 \quad 1$
$C. 4 \quad 1 \quad 2 \quad 3$
$D. 3 \quad 2 \quad 1 \quad 4$

Match the reactions in column $I$ with appropriate types of steps/reactive intermediate involved in these reactions as given in column $II$.
| Column $I$ | Column $II$ |
| :--- | :--- |
| $(A)$ $1-$phenylpentane$-1,4-$dione $\xrightarrow{aq. NaOH}$ $3-$phenylcyclopent$-2-$en$-1-$one | $(p)$ Nucleophilic substitution |
| $(B)$ $4-$chloro$-1-$phenylbutan$-1-$one $\xrightarrow{CH_3MgI}$ $2-$methyl$-2-$phenyltetrahydrofuran | $(q)$ Electrophilic substitution |
| $(C)$ $4-$hydroxy$-1-$phenylbutan$-1-$one $\xrightarrow{H_2SO_4}$ $2-$phenyl$-4,5-$dihydrofuran | $(r)$ Dehydration |
| $(D)$ $4-$methyl$-4-$phenylpentan$-1-$ol $\xrightarrow{H_2SO_4}$ $1,1-$dimethyl$-1,2,3,4-$tetrahydronaphthalene | $(s)$ Nucleophilic addition |
| | $(t)$ Carbanion |

If heterolytic and homolytic cleavage of a bond occurs,then which types of reactions occur?

Which of the following statements is not characteristic of free radical chain reaction?