What type of cross did Mendel use to determine the probability of offspring when investigating two characteristics at a time?

What is the difference between how ionic and covalent bonds form

With the word calcite wich completes the analogy mineral, erosion, marble, or aragonite

The fruit of a certain plant is sweet and fleshy. the seeds of this plant have a seed coat that is fairly tough. the seeds germinate better if they are exposed to acid, or scarification. what is the most likely type of dispersal for this seed? water animal wind