1. Aim/Purpose of the investigation To find out the relationship between the mass on a hanger and the stretch of a rubber band
2.
Which variable will be changed? (This is the independent variable)
Give the range of values you plan to use.
3.
What will be measured get some data or information from the investigation? (This is the
dependent variable)
How will it be measured or observed?
I
4. What other variables do you think are important in the investigation and will have to be
controlled to make it a fair test?
Variable
How will this variable be kept the same controlled) or measured?

Answerthe force between the charges will be  f/9 (one-ninth of force f)explanationcoulomb's law relates the magnitudes  two point charges q₁ and q₂, the distance, r, between the charges, and the electrostatic force, f, between the two charges:     k represents coulomb's constant, k = 8.99×10⁹ n·m²/c².note that if we have r = 3r, then   

The figure is missing but we can answer anyway.the correct answer is "releasing the string". in fact, when the person is holding the bow and the arrow, the kinetic energy of the arrow is still zero (because the arrow is not moving). the moment the arrow is released, it acquires a velocity v, so its kinetic energy will become different from zero: where m is the mass of the arrow and v its velocity.  all the other options, instead, do not increase the kinetic energy of the system: -  pulling farther back on the string : this will just increase the elastic potential energy of the system-  holding the arrow higher: this will increase the gravitational potential energy of the system (which is given by u=mgh, where h is the height above the ground)-  decreasing the mass of the arrow: this will decrease the gravitational potential energy of the system (which is given by u=mgh, where m is the mass)