A parking lot permits either cars or motorcycles. All together the vehicles parked in a particular day have 60 wheels. Use your reasoning and problem solving skills to find how many cars and how many motorcycles there could be in the parking lot this day.

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.