Plz someone help out

When can u say there is no solution for a system of linear inequalities? explain your answer and show with a system and graph

Two triangles can be formed with the given information. use the law of sines to solve the triangles. b = 49°, a = 16, b = 14

Aclassroom is made up of 11 boys and 14 girls. the teacher has four main classroom responsibilities that she wants to hand out to four different students (one for each of the four students). if the teacher chooses 4 of the students at random, then what is the probability that the four students chosen to complete the responsibilities will be all boys?