4.3 x 10 to the power of 2
Answer:
quadrilateral
Step-by-step explanation:
Caution: you need to use the same units of measurement throughout. If the spring stretches by 21 cm when a 135 newton object is attached, then you must ask for the mass (in newtons) of a fish that would stretch the spring by 62.1 cm.
We will need to assume that the spring is not stretched at all if and when no object is attached to the spring.
Write the ratio
21.0 cm 135 newtons
------------- = --------------------
62.1 cm x
Solve this for x. This x value represents the mass of a fish that would stretch the spring by 62.1 cm. You can cancel "cm" in the equation above:
21.0 135 newtons
------ = --------------------
62.1 x
Then 21.0x = (62.1)(135 newtons). Divide both sides of this equation by 21.0 to solve it for x.
Answer:
The correct option is D) 
Step-by-step explanation:
Consider the provided information.
People are entering a building at a rate modeled by f (t) people per hour and exiting the building at a rate modeled by g (t) people per hour,
The change of number of people in building is:

Where f(t) is people entering in building and g(t) is exiting from the building.
It is given that "The functions f and g are non negative and differentiable for all times t."
We need to find the the rate of change of the number of people in the building.
Differentiate the above function with respect to time:
![h'(x)=\frac{d}{dt}[f(t)-g(t)]](https://tex.z-dn.net/?f=h%27%28x%29%3D%5Cfrac%7Bd%7D%7Bdt%7D%5Bf%28t%29-g%28t%29%5D)

It is given that the rate of change of the number of people in the building is increasing at time t.
That means 
Therefore, 
Hence, the correct option is D) 