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.
Answer:
mechanical waves,
.
the quality of a sound governed by the rate of vibrations producing it; the degree of highness or lowness of a tone.
.
If the amplitude increases the volume increases and vice versa.
.
The type of medium affects a sound wave as sound travels with the help of the vibration in particles.
.
The higher the frequency, the shorter the wavelength.
Explanation:
Answer:
Explanation:
We need to find the energy for an electron to jump from n = 1 to n = 4.
The energy in transition from 1 state to another is given by :
The difference in energy for n = 1 to n = 4 is:
So, the required energy is equal to 
.
Answer:
Explanation:
Velocity of the ship is given as
the direction of the velocity of the ship is making an angle of 11 degree with the current
so we will have two components of the velocity
1) along the direction of the current
2) perpendicular to the direction of the current
so here we know that the component of the ship velocity along the direction of the current is given as
