BuilderBoi

For starters, don't shout "BRO I NEED HELP". 

Anyways, the answer is $\color {brown} \boxed{4}$, because the 2/5 and 3/5 sum to 1. 

Using trig, you have a triangle with a hypotenuse of 10, and an angle of 78. Doing $10 \times \sin(78) = o$

Solving, we find that it is 9.8 meters, or $\color{brown}\boxed{\text C}$

 2 - 2 - 6 triangle does not work, because 2 + 2 is less than 6.

Thus, the only working options are 3 - 3 - 4 and 2 - 4- 4, making $\color{brown}\boxed{2}$ options. 

It depends on your level.

I typically use Art of Problem Solving to practice math by playing Alcumus and watching videos every day. You just have to be focused on your goal of getting better at math.

Radius: $15.2 \div 2 = \color{brown}\boxed{7.6}$

Area: $7.6^2\times 3.14 = \color{brown}\boxed{181.3664}$

Circumference: $15.2 \times 3.14 = \color{brown}\boxed{41.728}$

I will take a shot at 1. 

Subsitute 1 as n. 

This gives: $5^2-1 \times a_2 = -1^1$

Solving for the unknown, we find $a_2 = 26$

Subsituting 2 for n, we get: $26^2-5a_3=-1^2$

Solving for the unknown again, we find $\color{brown}\boxed{a_3=135}$

Using the Pythagorean Theorem, the side length of the sqaure is $\sqrt{26}$, meaning that the square's area is: $\sqrt{26}^2 = \color{brown}\boxed{26}$