#3 Is insulators
#11 is conductors
This indeed is true, a hero is someone who can against very bad odds unify a country that can be torn or just be generally very heterogenous. There have been many cases of such heroes in the past where they would unify a certain country or society under the same banner.
Answer:
6N
Explanation:
Given parameters:
Pressure applied by the woman = 300N/m²
Area = 0.02m²
Unknown:
Force applied = ?
Solution:
Pressure is the force per unit area on a body
Pressure =
Force = Pressure x area
Force = 300 x 0.02 = 6N
Answer:
The pitch that he hears after the truck passes and is moving away is 819.6 Hz.
Explanation:
The pitch that he hears after the truck passes and is moving away can be calculated using the following equation:

Where:
: is the perceived frequency
: is the emitted frequency
: is the speed of sound = 340 m/s
: is the speed of the observer = 0 (he is not moving)
: is the speed of the fire truck
First, we need to find the speed of the fire truck. When it approaches the observer we have:




Hence, the speed of the fire truck is 25.05 m/s.
Now, we can calculate the pitch that the observer hears after the truck passes:



Therefore, the pitch that he hears after the truck passes and is moving away is 819.6 Hz.
I hope it helps you!