From here, it looks like all three sides of the right triangle are missing. I don't see any of them in the question.
Answer:

.
Step-by-step explanation:





Answer:
the rate of change of the water depth when the water depth is 10 ft is; 
Step-by-step explanation:
Given that:
the inverted conical water tank with a height of 20 ft and a radius of 8 ft is drained through a hole in the vertex (bottom) at a rate of 4 ft^3/sec.
We are meant to find the rate of change of the water depth when the water depth is 10 ft.
The diagrammatic expression below clearly interprets the question.
From the image below, assuming h = the depth of the tank at a time t and r = radius of the cone shaped at a time t
Then the similar triangles ΔOCD and ΔOAB is as follows:
( similar triangle property)


h = 2.5r

The volume of the water in the tank is represented by the equation:



The rate of change of the water depth is :

Since the water is drained through a hole in the vertex (bottom) at a rate of 4 ft^3/sec
Then,

Therefore,

the rate of change of the water at depth h = 10 ft is:




Thus, the rate of change of the water depth when the water depth is 10 ft is; 
Answer:
The diameter decreases at a rate of 0.053 cm/min.
Step-by-step explanation:
Surface area of an snowball
The surface area of an snowball has the following equation:

In which d is the diameter.
Implicit differentiation:
To solve this question, we differentiate the equation for the surface area implictly, in function of t. So

Surface area decreases at a rate of 3 cm2/min
This means that 
Tind the rate (in cm/min) at which the diameter decreases when the diameter is 9 cm.
This is
when
. So




The diameter decreases at a rate of 0.053 cm/min.
The correlation coefficient measures the relationship between the two variables
The correlation coefficient is 0.234
<h3>How to determine the correlation coefficient</h3>
The formula of correlation coefficient is:

Using the dataset from the complete question, we have:

Evaluate the difference

Evaluate the quotient

Approximate

Hence, the correlation coefficient is 0.234
Read more about correlation coefficient at:
brainly.com/question/4219149