To solve this problem you must apply the proccedure shown below:
1. You have that
varies jointly as
and
and inversely as the product of
and
. Therefore, you can write the following equation, where
is the constant of proportionality:

2. Now, you must solve for the constant of proportionality, as following:

3. Susbtiute values:


4. Substitute the value of the constant of proportionality into the equation:

The answer is: 
Answer:
He needs to makes sure both equal to 0.50 or less
Step-by-step explanation:
Answer:

Step-by-step explanation:
We want to model the position of the submarine as a function of time.
Notice that we have a constant amount. The initial depth: 750 meters
Then we have a factor that varies over time. Every hour the submarine ascends 50 meters. therefore as t increases the depth y(t) of the submarine decreases. Then the factor is:
-50t.
Where t represents the time in hours.
Then the equation that represents the new position of the submarine in relation to the level of the sea:

Answer:
Step-by-step explanation:
This is a d = rt problem; but since it is linear, then proportions will work too. Set up the proportion with miles on top and hours on the bottom:

Then put the numbers in where they go, keeping in mind that miles goes with miles and hours goes with hours in the ratios, and that our unknown is time (hours):
and cross multiply to solve:
638x = 4466 so
x = 7 hrs
Answer:
C
Step-by-step explanation:
A function passes the vertical line test. This graph passes it so it is a function.
A one to one function has a single output for each input. This has multiple outputs for some inputs. Therefore, it is not one to one.