If you guys could just help me with these four questions, that would help me out alot. Im not the the best mood right now. Thank you if you helped me out.

What is the area of triangle abc if a = 8, b = 11, and c = 15?

Teams of 4 are competing in a 1/4 mile relay race. each runner must run the same exact distance. what is the distance each teammate runs?

One number is 4 less than 3 times a second number. if 3 more than two times the first number is decreased by 2 times the second number, the result is 11. use the substitution method. what is the first number?