if you cross 2 heterozygous parents what is the possibility the offspring will be heterozygous as well

50 percent. If you make a Punnett square and put the genotypes Aa and Aa from the two heterozygous parents and combine them, you get the following results: AA, Aa, Aa, and aa. 2 of the four possible genotypes are heterozygous. 2/4=0.5. Fifty percent. Ta-da.