The graphs below have the same shape

Ineed if you could explain and give me the answer you! this needs done

What is the frequency of the sinusoidal graph?

Scores on the cognitive scale of the bayley-scales of infant and toddler development range from 1 to 19, with a standard deviation of 3. calculate the margin of error in estimating the true mean cognitive scale score, with 99% confidence, if there are 12 infants and toddlers in a sample.