Tree diagrams

Construct a tree diagram showing all the ways the names of three candidates; Alvin, Sally and Peter, can be listed on a ballot paper.

Construct a tree diagram showing all the ways a captain and a vice-captain can be selected from Matt, Rebecca, Helen and Chris.

Three cards labelled $\editable{2}$2, $\editable{3}$3 and $\editable{4}$4 are placed face down on a table. Two of the cards are selected randomly to form a two-digit number. The outcomes are displayed in the following probability tree.