Answer is B. second one
A = 1/8, B = 5/16, C = 7/12, D = 5/6
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Answer: B
Step-by-step explanation:
-1 will be your answer. (B)
So in 30 min will hike 2 1/4 miles =9 of those 1/4 miles therefore in 10 min will hike 9/3 =3 of those 1/4 miles = 3/4 of a mile
3/4 mile in 10 min;
(3/4)• 4 = 3 miles in 40 min;
6 miles in 80 min;
9 miles in 120 min;
12 miles in 160 min;
15 miles in 200 min;
18 miles in 240 min or 4 hours
Answer:
D = L/k
Step-by-step explanation:
Since A represents the amount of litter present in grams per square meter as a function of time in years, the net rate of litter present is
dA/dt = in flow - out flow
Since litter falls at a constant rate of L grams per square meter per year, in flow = L
Since litter decays at a constant proportional rate of k per year, the total amount of litter decay per square meter per year is A × k = Ak = out flow
So,
dA/dt = in flow - out flow
dA/dt = L - Ak
Separating the variables, we have
dA/(L - Ak) = dt
Integrating, we have
∫-kdA/-k(L - Ak) = ∫dt
1/k∫-kdA/(L - Ak) = ∫dt
1/k㏑(L - Ak) = t + C
㏑(L - Ak) = kt + kC
㏑(L - Ak) = kt + C' (C' = kC)
taking exponents of both sides, we have

When t = 0, A(0) = 0 (since the forest floor is initially clear)


So, D = R - A =

when t = 0(at initial time), the initial value of D =

Answer: a. $128.125
Step-by-step explanation:
The standard error of the mean is given by :
, where
= population standard deviation , n= sample size.
Given: 
n= 256
Then, the standard error of the mean:-

Hence, option a. is correct.