Sstt. SStt and sstt
For this, you need to draw a Punnett square and cross two parents' Ss tt.
St and st on each parent's place and cross them (photo).
You'll have an offspring 25% SStt, 50% Sstt, and 25% sstt.
If you say that capital S is dominant characteristic over lowercase s, you'll have 75% chances of the offspring showing it and only 25% of the offspring showing the recessive one.
