The correct answers are as follows: 1. The wave with the larger frequency IS THE ONE AT THE TOP. The frequency of a wave refers to the number of waves that is passing through a point in a certain time. The unit of frequency is Hertz. Looking at the diagrams above you will notice that the number of waves occurring per time in the top diagram is more that of the diagram below.
2. In the bottom wave, there are two complete wavelengths between 0 and 25 on the X axis. The first wavelength starts from the point where one is written on the Y axis and end at the opposite end of 1, the second wavelength starts from that point and end at the location corresponding to the top of figure 25 on the X axis.