Answer:
Tonya cut the cylinder vertically and David cut it diagonally.
The foreign investment is problematic for the economy of a transitioning country because it provides profit to the foreign investors only. They use cheap labor of the developing country. Moreover, the local producers and investors are directly harmed. The major profits are going in the pockets of the other nation's investors. This also causes inflation in the country.
Yo hablo un poco español, pero el solucion esta b) 351.6 pesos. 24x14.65 = 351.6
For two ratios to form a proportion they have to be equal.
To see if two ratios are equal we express them in their simplest form.
In this case we notice that in the first ratio both numbers are multiples of five, then:

In the second case we notice that both numbers are multiples of 2, then:

Since both ratios can be simplified to the same final ratio, they form a proportion.
X = 18°
cos 54° = sin 36°
cos 3 x = sin 2 x
cos ( 2 x + x ) = sin 2 x
cos 2 x cos x - sin 2 x sin x = 2 sin x cos x
( cos² x - sin² x ) cos x - 2 sin² x cos x = 2 sin x cos x / : cos x
( divide both sides by cos x )
cos² x - sin² x - 2 sin² x = 2 sin x
1 - sin² x - 3 sin² x - 2 sin x = 0
- 4 sin² x - 2 sin x + 1 = 0 substitution: u = sin x
- 4 u² - 2 u + 1 = 0
u = 2 -√20 / - 4
sin 18° = (√ 5 - 1 )/4 
cos 18° = √( 1² - ((√5 - 1)/4)²
cos 18° = (10+2√5)^(1/2) / 4