Answer:
2pq
Step-by-step explanation:
Hardy-Weinberg equation is p2+2pq+q2=1 (p+q=1).
p2 represents frequency of dominant homozygous (p is dominant allele), 2pq represents the frequency of heterozygous, q2 represents the frequency of recessive homozygous (q is the recessive allele).
So, in the example above, the frequency of heterozygous is 2*0.98*0.2=0.392