In right triangle ABC, m∠ B ≠ m∠ C. Let sin B = r and cos B = s.
What is sin C – cos C?

Imagine a new pasture with grass growing on it. every day after the seeds have germinated, the number of blades of grass in the pasture triples. after 18 days, the entire pasture is completely covered in grass. how many days did it take for the pasture to be one-third covered in grass?

Find the number of liters in 12.8 gal of gasoline. round to the nearest hundredths

In a two-digit number the units' digit is 7 more than the tens' digit. the number with digits reversed is three times as large as the sum of the original number and the two digits. find the number.