7^16/7^12=7^-18/? what is the missing denominator

If 10 men take 18 days to mow 60 acres of grass, how long will 15 men take to mow 80 acres?

Mike wants to make meatloaf. his recipe uses a total of 8 pounds of meat. if he uses a 3 to 1 ratio of beef to pork, how much pork will he use? enter your answer as a mixed number in simplest terms.

Given right triangle abc, what is the value of tan(a)?