We have that the the frequency of heterogeneou is mathematically given as
pq=0.45
From the question we are told
Generally the equation for the palleles Frequency is mathematically given as
p+q=1
q=0.65
Where
Hardy Weinberg Equation
p^2+q^2+2pq
0.12+0.42+0.45=1
Therefore
the frequency of heterogeneous is
pq=0.45
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