I need help please?

What is the answer to |-2x-5|-|-4+8| and x=7

What is the value of the expression below? (81^2)^1/8

Which formula finds the probability that a point on the grid below will be in the blue area? p(blue) = total number of squares number of blue squares number of blue squares p(blue) = total number of squares number of blue squares p(blue) = number of white squares