Help please I’ll mark brainiest

What is 20+(5 x 2/5 )+ 3 show your work

The bake stars picked 907 apples last weekend at a local orchard they made caramel apples and sold them in the bakery in trays of 6

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.