Will someone me ? i cant not fiqure it out and i need it done asap ☹️

Me find the value of x each figure.

Another type of subtraction equation is 16-b=7. explain how you would sole this equation then solve it.

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.