Answer:
The minimum initial speed of the marbles are 2.6 m/s
Step-by-step explanation:
Given that,
Height = 1.3 m
For vertical displacement,
We need to calculate the time
Using equation of motion

Put the value into the formula



We need to calculate the minimum initial speed of the marbles
Using formula of speed

Put the value into the formula


Hence, The minimum initial speed of the marbles are 2.6 m/s