Answer:
W = 311074.5 [J]
Explanation:
In order to solve this problem we must analyze two parts, in the first part by means of Newton's second law we can determine the acceleration of the beam, remembering that the sum of the forces is equal to the product of mass by acceleration.
∑F = m*a
F = forces acting on the beam [N]
m = mass = 425 [kg]
a = acceleration = 1.8 [m/s²]
The forces acting on the beam are the force of the crane up (positive) and the weight of the beam down (negative)
![F_{crane}-(425*9.81)= 425*1.8\\F_{crane}=4713.25 [N]](https://tex.z-dn.net/?f=F_%7Bcrane%7D-%28425%2A9.81%29%3D%20425%2A1.8%5C%5CF_%7Bcrane%7D%3D4713.25%20%5BN%5D)
Now in the second part, we use the definition of work, which is equal to the product of the force applied in the direction of displacement, that is, the product of force by distance.

where:
W = work [J]
F = force = 4713.25 [N]
d = distance = 66 [m]
![W=4713.25*66\\W=311074.5[J]](https://tex.z-dn.net/?f=W%3D4713.25%2A66%5C%5CW%3D311074.5%5BJ%5D)
Answer:B,C,D
Explanation:
Thermodynamic efficiency is given by

efficiency can be increased by Keeping
constant and increasing 
Keeping
constant and decreasing
by increasing 
by decreasing
ratio
Answer:
A horse pulls a cart, a person walks on the ground
Explanation:
Answer:
OD. The process of cutting down irrelevant information so only the information that is useful for particular purpose remains
Answer:
it wont be because the hand brake would be on