Answer:
1661.06 cm²
Step-by-step explanation:
From the question given above, the following data were obtained:
Radius (r) = 11.5 cm
Size of synthetic leather needed =?
To know how many square centimetres of synthetic leather needed to cover the ball, we shall determine the area of the ball. This can be obtained as follow:
Radius (r) = 11.5 cm
Pi (π) = 3.14
Area of ball =?
The shape of a ball is spherical in nature. Thus, we shall apply the formula for calculating the area of a sphere. This is illustrated below:
A = 4πr²
A = 4 × 3.14 × 11.5²
A = 4× 3.14 × 132.25
A = 1661.06 cm²
Thus, 1661.06 cm² of synthetic leather needed to cover the ball.
Sam=3syd+6 and sam=36, since sam=sam we can say:
3syd+6=36
3syd=30
syd=10
So Sydney has 10 pieces of candy.
Answer:
Population in 2100 is 17.99 billion.
Step-by-step explanation:
The population of the world in 2020 = 7.8 billion.
The growth rate = 1.05%
Now find the population after 2100. Use the below formula to find the population.
Population in 2100 = Population of 2020 (1 + growth rate)^n
Population in 2100 = 7.8 (1 + 0.0105)^80
Population in 2100 = 17.99 billions.
Now, find the growth rate in 2100.
dN/dt = [r N (K – N) ] / K
r = Malthusian parameter
K = carrying capacity.
Now divide both sides by K, now x = N/K then do the differential equation.
dx/dt = r x ( 1- x)
Now integrate, x(t) = 1/ [ 1 + (1/x – 1) c^-rt
From the first equation = dN/dt = (13 – 7.8) / 80 = (r × 7.8×(13 – 7.8) / 12
0.065 = (r × 7.8× 5.2) / 12
0.065 = r × 3.38
r = 1.92%
