Respuesta :
Answer:
1st question: 2 years old
2nd question: 3 years old
Explanation:
The answer to the first question is 2 years old because a kid has the muscles which allow him to start jumping. Most usually this happens between the ages of 2 and 3.
The answer to the second question is 3 years old because at that age the kid acquires the coordination and strength that is necessary to balance on a tricycle.