Which of the following would not produce a magnetic field

Awater balloon launcher uses an elastic band with a spring constant of 115 n/m to use thee launcher you stretch thee band back with a balloon n it the water balloons have a mass of 1.3 kg a) if you stretch the band by 0.8 m, what elastic force will the band exert? b) with the band stretched 0.8 m, how much elastic potential energy is stored in the spring? c) if you release the band, it pushes forward. what is the kinetic energy of the balloon when it reaches the natural length of the band? d) what is the speed of the balloon when it reaches the natural length of the band?

Which of the choices are parts of an atom? select all that apply. a.) compound b.) electron c.) neutron d.) molecule e.) photon f.) proton g.) element

Efficiency is the ratio of to for a system a)power in to power in b)power in to power out c) power out to power out d) power out to power in