Answer:
215 students
Step-by-step explanation:
500 divided by 2 = 250
250 - 35 each= 215
Answer:
A = 64 pi
or approximately 200.96
Step-by-step explanation:
The diameter is twice the radius
d = 2r
16 = 2r
Divide by 2
16/2 = 2r/2
8 =r
The area of a circle is
A = pi *r^2
A = pi*(8)^2
= pi *64
Or if we approximate pi as 3.14
A = (3.14) * (64)
A = 200.96
Answer:
Q(t) = Q_o*e^(-0.000120968*t)
Step-by-step explanation:
Given:
- The ODE of the life of Carbon-14:
Q' = -r*Q
- The initial conditions Q(0) = Q_o
- Carbon isotope reaches its half life in t = 5730 yrs
Find:
The expression for Q(t).
Solution:
- Assuming Q(t) satisfies:
Q' = -r*Q
- Separate variables:
dQ / Q = -r .dt
- Integrate both sides:
Ln(Q) = -r*t + C
- Make the relation for Q:
Q = C*e^(-r*t)
- Using initial conditions given:
Q(0) = Q_o
Q_o = C*e^(-r*0)
C = Q_o
- The relation is:
Q(t) = Q_o*e^(-r*t)
- We are also given that the half life of carbon is t = 5730 years:
Q_o / 2 = Q_o*e^(-5730*r)
-Ln(0.5) = 5730*r
r = -Ln(0.5)/5730
r = 0.000120968
- Hence, our expression for Q(t) would be:
Q(t) = Q_o*e^(-0.000120968*t)
Answer:
She could plant 9 plants.
Step-by-step explanation:
1 1/2 hours = 90 minutes, so 12 plants per 90 minutes. Which would mean 6 plants per 45 minutes. So in between 45 and 90 minutes (1 hour), and in between 6 and 12 plants (9).
Sorry if you didn't understand, I'm bad at explaining.
2(1/3+6a)
this is the answer
