Please help using law of cosines

Ineeeeed this is due tomorrow and i dont know the answer can you find all the exponents

Apatient is to be given 35 milligrams of demerol every 4 hours. you have demerol 50 milligrams/milliliter in stock. how many milliliters should be given per dose?

The point of intersection of the diagonals of a rectangle is 4 cm further away from the smaller side then from the larger side of the rectangle. the perimeter of the rectangle is equal to 56 cm. find the lengths of the sides of the rectangle. 16 points answer quick