Class, As the classification system goes phylum (eg. chordata), class (eg. mammalia), order (eg. carnivora), family (eg. felidae), genus (eg. panthera), species (eg. leo) and all the following are in the same class- mammalia
Start the stopwatch just after a wave reaches the pier.count 10 more wave speak reaches the pier.<span> Stop the stopwatch when the 10th peak reaches the pier. </span>
<span>Period of one wave = P = (Time measured) ⁄ 10 </span>
<span>Frequency = f = 1 ⁄ P</span>
