Answer
See attachment
Work Step by Step
The strength of each signal in the mass spectrum of the sample is proportional to the natural abundance of that particular isotope.
$x_{296_{Wt}}= \frac{N_{296_{Wt}}}{N_{total}}= \frac{36}{50}= 0.72$
$x_{297_{Wt}}= \frac{N_{297_{Wt}}}{N_{total}}= \frac{2}{50}= 0.04$
$x_{298_{Wt}}= \frac{N_{298_{Wt}}}{N_{total}}= \frac{12}{50}= 0.24$