One subtask in the game is to roll the dice. explain why is roll the dice an abstraction.

A game is built from a combination of sub-tasks in order to provide the best experience to the user and make sure that the interface is comprises of only the results of the ongoing sub-tasks to provide a higher degree of data abstraction.

Data abstraction refers to the process of representing the essential information without including the background details. Rolling a dice is preferred to be a sub-task so that the user only gets to know about the result of the roll and does not have to wait for or anticipate the result. Moreover, a game may consist of n number of sub-tasks so it is not a good idea to include them in the main framework and are preferred to be abstracted.

the major difference between the two is the objective and the reward of the game. candy crush has a puzzle theme with the objective of meeting a specific quota of points or objects, you are able to gain access to the next level and compete with peers on the process. on duolingo the objective is rather different, you are given sets of questions for you to answer for you to move to the next level and as for the reward, you are able to learn available language as this is an app developed to teach the user about other languages.