When a wave has a height of 5 feet and a wavelength of 15 feet then it has a wave base of 7.5 feet. Wave base is equal to the half of the wavelength so if you consider your wavelength to be 15 feet then it is divided into 2 that would give you answer of 7.5 feet.
In active transport, materials move from an area of high concentration to an area of lower concentration (goes down the concentration gradient) and it requires or uses energy in the form of ATP (adenosine triphosphate)
