Answer:
Step-by-step explanation:
Not sure what form you need this in, but it really doesn't matter, as you'll see in the final equation. I used the vertex form and solved for a:

We are given the vertex (h, k) as the origin (0, 0), and we have a point that the graph goes through as (4, -64). That's our x and y. Plugging in what we have:
gives us
-64 = 16a and
a = -4. That means that the quadratic equation is
which is both vertex form and standard form here, no difference.
An ecosystem is a community of living organisms in conjunction with the nonliving components of their environment, interacting as a system. These biotic and abiotic components are linked together through nutrient cycles and energy flows. ... Ecosystems are controlled by external and internal factors.
The given MGF is that for a random variable following a Poisson distribution with parameter

.
This means

, and

has PMF

So, the desired probability is

This is equivalent to
Let us assume the number to be = x
Then
(80/100) * x = 56
4x/5 = 56
4x = 56 * 5
4x = 280
x = 280/4
= 70
The value of the unknown number is 70. I hope the procedure is clear enough for you to understand. You can always use this method for solving similar problems in future without requiring any help from outside. Only thing that needs to be taken care of is the calculation part.