Answer: Some challenges that I could see would be the walls, possibly a moat, tar, and the towers.
Explanation: The wall is obliviously a main problem, trying to get over it or through it is a difficult challenge. The moat (if it has one) means that there is more than likely only one way to get in or out. If it does have tar it means that the attackers are going to be put in a "sticky situation" And finally the towers, they have people at the top shooting arrows down at you, or throwing things at you.
Heat normally travels from areas of higher heat to areas of lower heat. For example, if you were to be in a classroom and all the windows and doors were closed, and then you opened a door, then the reason why the room becomes cooler is not because cold air comes inside the room. However, it is because when you open the door, the heat from the classroom you're in escapes the room. This is why it feels cooler when you open a door, or even a window. Heat is traveling from areas of higher heat to areas of lower heat.
Answer: 1.289 m
Explanation:
The path the cobra's venom follows since it is spitted until it hits the ground, is described by a parabola. Hence, the equations for parabolic motion (which has two components) can be applied to solve this problem:
<u>x-component:
</u>
(1)
Where:
is the horizontal distance traveled by the venom
is the venom's initial speed
is the angle
is the time since the venom is spitted until it hits the ground
<u>y-component:
</u>
(2)
Where:
is the initial height of the venom
is the final height of the venom (when it finally hits the ground)
is the acceleration due gravity
Let's begin with (2) to find the time it takes the complete path:
(3)
Rewritting (3):
(4)
This is a quadratic equation (also called equation of the second degree) of the form 
, which can be solved with the following formula:
(5)
Where:
Substituting the known values:
(6)
Solving (6) we find the positive result is:
(7)
Substituting (7) in (1):
(8)
We finally find the horizontal distance traveled by the venom:
