Please guys i really need your help for this question

Asap will give brainiest to first person to answer what is the measure of angle b in the triangle? enter your answer in the box.m∠b=

Ineed some on this. not sure how to solve.

The bottom of ignacio's desktop is 74.5cm from the floor. ignacio's sits in his adjustable chair, and the tops of his legs are 49.3cm from the floor. each clockwise rotation of the knob on the chair raises ignacio's legs by 4.8cm. write an inequality to determine the number of clockwise rotations, r, ignacio could make with the knob without his legs touching the desk