See the picture attached to better understand the problem
we know that
in the right triangle ABC
cos A=AC/AB
cos A=1/3
so
1/3=AC/AB----->AB=3*AC-----> square----> AB²=9*AC²----> equation 1
applying the Pythagoras Theorem
BC²+AC²=AB²-----> 2²+AC²=AB²---> 4+AC²=AB²----> equation 2
substitute equation 1 in equation 2
4+AC²=9*AC²----> 8*AC²=4----> AC²=1/2----> AC=√2/2
so
AB²=9*AC²----> AB²=9*(√2/2)²----> AB=(3√2)/2
the answer isthe hypotenuse is (3√2)/2
As we already have the model that describes the change of the population in Italy in terms of the years that have elapsed, we only have to replace the conditions that are requested in that equation.
Therefore to find the population of Italy in the year 2000 (t = 10 years) substitute t = 10 in the equation and have:

million people
To find the population of Italy in 2008 (t = 18 years)
substitute t = 18 in the equation and have:

million people
To predict the population in Italy for 2015 and 2020 with this model, we substitute in the equation t = 25 and t = 30
t = 25
million people
t = 30
million people
Answer: The top of the Crane is 31 feet above the ground.
Step-by-step explanation:
When it is fully extended, the crane arm forms a 30 degree angle with a line parallel to the ground. This means that a right angle triangle is formed. The length of the Crane's arm represents the hypotenuse. The horizontal distance represents the adjacent side of the right angle triangle. The distance, h of the top of the Crane from the ground represents the opposite side of the right angle triangle.
To determine h, we would apply
the Sine trigonometric ratio.
Sin θ, = opposite side/hypotenuse. Therefore,
Sin 30 = h/62
h = 62Sin30
h = 62 × 0.5
h = 31 feet