What’s the answer for the circled questions

What is the equation of the graph below? y=sec(x)-4

Jack did 3/5 of all problems on his weekend homework before sunday. on sunday he solved 1/3 of what was left and the last 4 problems. how many problems were assigned for the weekend?

Kendra had twice as much money as kareem. kendra later spent $8 and kareem earned $6. by then, the two had the same amount of money. how much money did each have originally?