Express (4/3x-4 )^2 as a trinomial in simplest form.

Really need on these. i have no idea what to do

Select all the correct statements. the amount in dollars an electrician charges in terms of the number of hours worked is represented by the function y = 22x + 42. from the function, identify all the phrases that hold true for the situation. the electrician charges an initial fee of $22 the y-variable represents the number of hours the electrician charges an initial fee of $42 the electrician charges $22 for every hour worked the x-variable represents the electricians charges in dollars the electrician charges $42 for every hour worked

Ibeg you to me 20. a reaction produces 4.93 l of oxygen, but was supposed to produce 1 mol of oxygen. what is the percent yield?