You need to know more information, not just the length of the hypotenuse.
If you know the length of one leg use Pythagoras theorem to find the other.
If you know the value of one other angle use trigononemtry
Answer:
The number of 1/5 liter glasses that Lin can fill is 
Step-by-step explanation:
we know that
To find out how many 1/5 liter glasses can Lin fill with a 1 1/2 liter bottle of water, divided 1 1/2 by 1/5
so

Convert mixed number to an improper fraction

substitute

Multiply in cross

Convert to mixed number

Answer:
D. sin m∠C = 2 square root of 5 all over 5
Step-by-step explanation:
The triangle ABC is a right angled triangle. The angle ∠C is where we are asked to find. The side AB measures 6 , AC measures 3 and the side BC measures 3√5.
The longest side of a right angle triangle is the hypotenuse, that means the side with length 3√5 is the hypotenuse.
Therefore side BC is the hypotenuse side and we are asked to find the angle C. AB is the opposite side while AC is the adjacent side.
Using
sin C = opposite/hypotenuse = 6/3√5 = 2/√5 = 2√5/5
cos C = adjacent/hypotenuse = 3/3√5 = 1/√5