Answer:
B. establish communes and promote labor-intensive agriculture
For cities, mountains can be both a help and hindrance. Whilst mountains can be a barrier to trade and transport, they form a natural line of protection from invasion. Therefore, many ancient cities thrived when located near mountains, with the reduced risk of attack affording them time to grow and prosper
The free body diagram consists of:
1) Weight force, which is a vertical arrow downward
2) A Normal force that is perpendicular to the ramp.
The Normal force can be decomposed in a vertical component and an horizontal component.
The vertical component, Ny, must equal the weight force, due to equilibrium (rest) condiition =>
Ny = weight = m*g = 5.5kg*9.8m/s^2 = 53.9 N
By geometry the vertical component of the Normal force, Ny is such that
cos (angle) = N / Ny => N = Ny * cos(angle)
=> N = 53.9N * cos(angle)
Now use that equation for each option:
a) 0 ° => N = 53.9N * cos(0) = 53.9N
b) 12° => N = 53.9 * cos(12) = 52.7N
c) 25° => N = 53.9 * cos(25) = 48.9N
d) 45° => N = 53.9 * cos(45) = 38.1N
Ice was produced using radiation effect by setting out shallow terra cotta rays with just small amount of water. At night when the temperatures were cool while humidity is low the water used to freeze in the morning.the ice formed was collected and stored in caverns
