Given an advanced sinusoidal wave to the left of the string, with an amplitude of 1.4 cm, a wavelength of 40 cm and a frequency of 20 Hz. It is known that at time t = 0 at point 0 = x the copy is reset and the string moves upwards. A. Write the function that describes the copy of each point X in the string as a function of time t. Express using the variables x, t and the numerical data in question. Write down the units of each number. B. Calculate the velocity of the point at the beginning C. What is the copy at point x 5 cm at time t = 3 sec? the axes at time t = 0.