Approximately how many centiliters are in 3 quarts? round answer to the nearest unit.

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

What is the perimeter of an equilateral triangle if each side is (x+3)?

Asource of laser light sends rays ab and ac toward two opposite walls of a hall. the light rays strike the walls at points b and c, as shown below: what is the distance between the walls?