Answer:

& 
Explanation:
Given:
- interior temperature of box,

- height of the walls of box,

- thickness of each layer of bi-layered plywood,

- thermal conductivity of plywood,

- thickness of sandwiched Styrofoam,

- thermal conductivity of Styrofoam,

- exterior temperature,

<u>From the Fourier's law of conduction:</u>

....................................(1)
<u>Now calculating the equivalent thermal resistance for conductivity using electrical analogy:</u>




.....................(2)
Putting the value from (2) into (1):


is the heat per unit area of the wall.
The heat flux remains constant because the area is constant.
<u>For plywood-Styrofoam interface from inside:</u>



&<u>For Styrofoam-plywood interface from inside:</u>



It’s true all the way. It’s true
Power is defined as the rate at which the body is doing work:

Work is defined as displacement done by the force times that displacement:

We know that we need 62N to move the box, so when we apply this force along the path of 10m we have done:

of work.
Now we just divide that by 5s to get how much power is required:
B: Extension Lines! You could have just searched this up on google