Answer:
(a) Hypergeometric distribution
(b) 0.785384...
Step-by-step explanation:
(a) looking at the question, we see that
, suppose Evans studied s key terms, this implies that he has not studied 100 - s key terms. Suppose
if X = k, then k out of the s key terms he had studied appeared. But 10 - k out of 100 - s key terms he hasn't studied appeared. Thus X is an Hypergeometric distribution, X~HGeom(s, 100 - s, 10) with PMF:

It’s the third graph down!!
X = -8
since you know that it’s a vertical line, it’s going to be x = _. since -8 is the x coordinate, the equation is x = -8. hope this helped!
Answer:
ef`
Step-by-step explanation:
e^4xf÷e^3xf^2
e^4f÷e^3f^2
ef`

Taking natural logs of both sides, we get
0.015t=ln 3
t = ln 3/0.015 = 73.24
The answer is 73.24 years.