Can you please help me with 10 and 11?

Tickets to a science exposition cost $5.75 each for studentd and $7.00 for adults.how many students and adults went if the ticket charge was $42.75

The cost of using a service is $0.25 per min. what equation correctly represents the total cost c, in dollars, for d days of use?

Tamar is measuring the sides and angles of tuv to determine whether it is congruent to the triangle below. which pair of measurements would eliminate the possibility that the triangles are congruent