Answer in Python:
# Define program constants
PI = 3.14
# Welcome the user to our program
print("### Welcome to the Sphere Volume Calculator")
# Ask for the Radius (r) input and store it as a float
radius = float(input("Type the Radius of your sphere in meters: "))
# Calculate the volume
volume = 4 / 3 * PI * radius ** 3
# Print the result
print("Your sphere volume is:", volume, "m³")
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