Does anyone know the answer to this question?

D. 3 √3

I'm using the Pythagorean theorem wherein: a² + b² = c² (hypothenus)

a = unknown
b = 3
c = 6

a² + 3² = 6²
a² = 6² - 3²
a² = 36 - 9
a² = 27
a = √27

a = √9 * 3
a = 3 √3

The answer is 0 quarts.

Remember
1 gallon contains 64ounces
1 cup contains 8ounces
1 pint contains 16ounces

We know that 2 gallons (128oz total) are needed to fill the bucket.

First, Omar pours 64 ounces into the bucket so we have 128 - 64 = 64 ounces left to fill.

Second, Penny pours 8 cups which is the same as 64 ounces (8cups x 8 ounces = 64 ounces total) into the bucket.

Stop here and add up the water in the bucket.

The bucket has only 128 ounces capacity total which means Omar and Penny have filled up the bucket with 64 ounces each. 64 x 2 = 128 ounces

The bucket is full, Ronnie actually makes it overflow. So Sierra will pour 0 quarts of water into the bucket.