Answer:
<em>The average speed is 22.2 km/h</em>
Explanation:
<u>Average Speed</u>
Given an object travels a total distance d and took a total time t, then the average speed is:

The mailman first drives d1=7 km at v1=15 km/h. The time taken to drive is:

Then he drives d2=7 km at v2=43 km/h taking a time of:

The total time is
t=0.467 h + 0.163 h = 0.63 h
The total distance is
d = 7 km + 7 km = 14 km
The average speed is:

The average speed is 22.2 km/h
Answer:
Pressure difference between Top and Bottom of the cylinder is given as

Explanation:
As we know that the force due to pressure is balanced by the weight of the cylinder
So we will have

so we have

so we have

so we have

The best way to deterime which cloth with absorb heat is to put each cloth outside in the heat with a thermometer under it and see which has the highest tempe.
Answer:

Explanation:
We know that impedance of a RLC circuit is given by 
So
here R is resistance
is inductive reactance and
is capacitive reactance
To minimize the impedance
should be zero we know that 
So 


We know that 
So 

Where f is resonance frequency