What did Mendel produce when he cross-bred different true-breeding plants

Ineed ! i have no clue how to do this problem.

When a device is used in a circuit in which the voltage is 81 v the current flowing through the device is 3 a what is the resistance of the device

Which factor is likely to impact the possible number of compounds? presence of unlimited number of elements in the periodic table the inability of atoms to align perfectly with other atoms the ability of all elements to react with every other element all elements being equally reactive