Answer: 75%
Step-by-step explanation:
Heterozygous means that one allele would be dominant, and the other would be recessive. I will use B for the dominant allele, and b for the recessive allele.
Next, create a Punnett square (look at the pic).
To make the Punnett square, draw a 2 × 2 table. Put Bb on the top (one over each column) and Bb on the left side (one next to each row). Cross multiply. Remember to always put the dominant allele (in this case, B) in front of the recessive allele (in this case, b). The dominant allele will always be exhibited in the organism. So, the answer is 75%, since 3/4 of the different combinations of alleles is long ears.