The cornea is shaped like a dome and bends light to help the eye focus. Some of this light enters the eye through an opening called the pupil (PYOO-pul). The iris (the colored part of the eye) controls how much light the pupil lets in. Next, light passes through the lens (a clear inner part of the eye).
Only velocity uses direction of travel in its calculations.
Frequency = rate of sploosh = 2 per second = 2 Hz.
Period = ( 1/frequency ) = 1/2 second
Speed = (wavelength) x (frequency) = (0.15m) x ( 2/sec) = 0.075 m/s .
Answer:
I think its (A)The specific heat of an object explains how easily it changes temperatures.
Explanation:
Let us consider two vectors A and B.
As per the question, the two vectors are perpendicular to each other.
Hence the angle between them 
We are asked to calculate the resultant of these two vectors.
As per parallelogram law of vector addition, the resultant of two vectors are-

[cos90=0]

This is the way by which we can add two perpendicular vectors.