Geometry find the measure of angle t for both triangles

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

In each diagram, line p is parallel to line f, and line t intersects lines p and f. based on the diagram, what is the value of x? ( provide explanation)

Benefit(s) from large economies of scale, in which the costs of goods decrease as output increases. natural monopolles perfect competition