solve the equation

a) It is known that the standard deviation for a set of data is 2.8. Find the variance for the dat b) If the lowest value in a set of data is 25, and the range for the same data is 18, find the higl the set. [1 mark] c) Adult 1C1 scores have a bellshaped distribution with a mean of 120 and a standard deviatio the empirical rule to find the percentage of adults with ID. scores between 60 and 180. lnclud with your answer (leave no space between the number and the symbol of percentage). d] Adult IO. scores have a bell-shaped distribution with a mean of 120 and a standard deviatio What IQ score is positioned 1.8 standard deviations above the mean? > [ f