Answer:
+
Step-by-step explanation:
++ = +
+- = -
-+ = -
-- = +
Example:
-1 x -1 = 1
1 x -1 = -1
Answer:
7.5mi
Step-by-step explanation:
Answer:
a) Depth changing rate of change is 
, When the water is 6 meters deep
b) The width of the top of the water is changing at a rate of 
, When the water is 6 meters deep
Step-by-step explanation:
As we can see in the attachment part II, there are similar triangles, so we have the following relation between them 
, then 
.
a) As we have that volume is 
, then 
, so we can derivate it 
due to the chain rule, then we clean this expression for 
and compute with the knowns 
, is the depth changing rate of change when the water is 6 meters deep.
b) As the width of the top is 
, we can derivate it and obtain 
The width of the top of the water is changing, When the water is 6 meters deep at this rate
