Thank you for reporting, we will resolve it shortly
Q.
A carrier wave of peak voltage $14\, V$ is used for transmitting a message signal. The peak voltage of modulating signal given to achieve a modulation index of $80\%$ will be:
Amplitude of carrier wave is $A_{ c }=14\, V$
Index is $\mu=80 \%=0.80$
Amplitude of modulating signal is given by
$\mu=\frac{A_{ m }}{A_{ c }}$
$\Rightarrow A_{ m }=\mu A_{ c }$
$\Rightarrow A_{ m }=0.8 \times 14=11.2\, V$