I need help I don’t understand how to do this for my test

Renita analyzed two dot plots showing the snowfall during the winter months for city a and for city b. she found that the median snowfall is 5 inches less in city a than in city b. the mean snowfall is about 2 inches less in city a than in city b. which explains why there is a difference in the measures of center for the sets of data?

What is 1/2 x (6 x 4)+3 + 2 show your work

Evaluate the expression for the given value of the variable 7a - 4a for a =8