To solve this problem it is necessary to apply the concepts related to rate of thermal conduction

The letter Q represents the amount of heat transferred in a time t, k is the thermal conductivity constant for the material, A is the cross sectional area of the material transferring heat,
, T is the difference in temperature between one side of the material and the other, and d is the thickness of the material.
The change made between glass and air would be determined by:





There are two layers of Glass and one layer of Air so the total temperature would be given as,




Finally the rate of heat flow through this windows is given as,



Therefore the correct answer is D. 180W.
Answer:
Distance, d = 112.5 meters
Explanation:
Initially, the bicyclist is at rest, u = 0
Final speed of the bicyclist, v = 30 m/s
Acceleration of the bicycle, 
Let s is the distance travelled by the bicyclist. The third equation of motion is given as :



s = 112.5 meters
So, the distance travelled by the bicyclist is 112.5 meters. Hence, this is the required solution.
Answer:
C) 26.6
Explanation:
I don't know how to calculate vector
The speed of sound at T=25°C is Vs=346 m/s. So the sound has to reach the cliff and return back to you so the path it needs to travel is s=2*440 m = 880 m.
Since the speed of sound is constant s=Vs*t, and t= s/Vs=880/346=2.54335 s. You will hear the echo after t=2.54335 s after you shouted.