As a experiment you could use is The affect of light in plants. A study He can do is maybe about Gravity affects and how it works on weight. Also you can do a all time favorite the Mentos and Diet Coke Experiment.
Hopefully one of these ideas will inspire you!
Use Scoratic it works with any time of subject
I think that the answer is A
Acceleration I think if I’m not mistaken
Answer:half of shorter Pipe
Explanation:
Fluid is Flowing through two horizontal pipes with pressure difference

Both pipes have same radius
Length of one Pipe is twice of other
Let Longer Pipe be denote by 1 and smaller by 2
From Hagen Poiseuille equation

Where
viscosity of medium
L=length of Pipe
Q=discharge
D=diameter
For longer Pipe
----1
For smaller Pipe
------2
From 1 & 2 we get


volume flow rate of longer pipe is half of smaller pipe