2 1/6 + (-5/6)= what’s the answer I need help ASAP

Which of the following is the best first step in solving the equation below? 4+2㏒³x=17

See attachment below and find the equivalent of tan(∠qsr)

From the top of a tree a bird looks down on a field mouse at an angle of depression of 50°. if the field mouse is 40 meters from the base of the tree, find the vertical distance from the ground to the bird's eyes.