Aship travels with velocity given by [12], with current flowing in the direction given by [11] with respect to some co-ordinate axes. what is the velocity of the ship in the direction of the current?

just took the test its not "d"

answer: the correct answer for the fill in the blank is rods.

rods are the specialized photoreceptor cells that are present in the retina of human eye. they are responsible for vision in the night time ( also called scotopic vision). they have very low visual acuity and color distinguishing ability.

as they are responsible for vision in night time, therefore they are found predominantly in the nocturnal animals.