Added Record Time Function.
Product for kids challenging addition for the first time.
There are three modes.
*Easy : The addition using numbers from 1 to 5. (5 questions)
*Normal : The addition using numbers from 3 to 9. (10 questions)
*Hard : The addition using numbers from 5 to 14. (10 questions)
The Record Time is updated In the case of an all correct answer.
In the case of an all correct answer, you obtain the first star.
In the case of an all correct answer within 30 seconds, you obtain the second star.
