Trigonometric ratios: fixed and variable acute angle this activity will you meet these educational goals: stem—you will apply mathematical and technology tools and knowledge to analyze real-world situations. 21st century skills—you will use critical-thinking and problem-solving skills. directions read the instructions for this self-checked activity. type in your response to each question, and check your answers. at the end of the activity, write a brief evaluation of your work. activity question 1 when designing a truss, a truss builder might know the base angle measurement and the length of the tie beam needed. the next step is to compute the height of the king post. let's take a look at some right triangles to see whether knowing the measure of an acute angle of a right triangle and the length of one of the sides is enough to find the lengths of the other two sides. you will use geogebra to explore the trigonometric ratios when an acute angle is fixed for a given right triangle. go to trigonometric ratios, and complete each step below. the right triangle represents half of a king post truss. if you need , follow these instructions for using geogebra. part a what is the measure of ∠bac?