PLZ HELP ITS A K12 QUESTION

Nnnnneeedd 1.find the residual if you know the actual number is 5.2 and the predicted value is 4.8

If f(x)=x^3 and g(x)=2x+7 when g(x)=-5

Someone this asap for a group of students attends a basketball game. * the group buys x hot dogs at the concession stand for $2 each. * the group buys y drinks at the concession stand for $3 each. the group buys 29 items at the concession stand for a total of $70. how many hot dogs did the group buy?