Please help.. 5 questions are in each picture. Only answer if you really know. Anwer all

Express the following as a function of a single angle, cos(60) cos(-20) - sin(60) sin(-20)

When the solutions to each of the two equations below are graphed in the xy-coordinate plane, the graphs of the solutions intersect at two places. write the y-cordninates of the points of intersection in the boxes below in order from smallest to largest. y=2x y=x^2-3

Sara can take no more than 22 pounds of luggage on a trip. her suitcase weighs 112 ounces. how many more pounds can she pack without going over the limit?