Answer:
Volume of balloon = 1000 cm^3
Explanation:
The head of a normal person can be assumed as a sphere with radius 10 cm.
Volume of sphere
, where r is the radius.
We have approximate radius = 10 cm.
Approximate volume of head 
In the given options the closest value to the approximate volume is 1000 cm^3.
So, volume of head = Volume of balloon = 1000 cm^3
Mass/volume is density so it’s 562g/72cm^3 so it’s roughly 7.805g per cubic centimeter
Complete Question
A person throws a pumpkin at a horizontal speed of 4.0 m/s off a cliff. The pumpkin travels 9.5m horizontally before it hits the ground. We can ignore air resistance.What is the pumpkin's vertical displacement during the throw? What is the pumpkin's vertical velocity when it hits the ground?
Answer:
The pumpkin's vertical displacement is 
The pumpkin's vertical velocity when it hits the ground is 
Explanation:
From the question we are told that
The horizontal speed is 
The horizontal distance traveled is 
The horizontal distance traveled is mathematically represented as

Where t is the time taken
substituting values

=> 

Now the vertical displacement is mathematically represented as

now the vertical velocity before the throw is zero
So


Now the final vertical velocity is mathematically represented as

substituting values


Static friction and normal force? I would Google to double check if I'm right.