1.12 m/s is the velocity. You can get the velocity of a wave by multiplying the frequency and wavelength together. The product is the velocity.
Answer: v = 
Explanation: q = magnitude of electronic charge = 
mass of an electronic charge =
V= potential difference = 4V
v = velocity of electron
by using the work- energy theorem which states that the kinetic energy of the the electron must equal the work done use in accelerating the electron.
kinetic energy =
, potential energy = qV
hence, 

120 volts for most home a phone charger can convert 120 volts ac to 5 volts dc
C . Record the time to complete a chemical reaction