Answer:
28atm
Explanation:
Using Gay lussac's law equation as follows:
P1/T1 = P2/T2
Where;
P1 = initial pressure (atm)
T1 = initial temperature (K)
P2 = final pressure (atm)
T2 = final temperature (K)
Based on the information provided in this question;
P1 = 30.0 atm, T1 = 30.0°C, P2 = ?, T2 = 10.0°C
NOTE: Absolute temperature i.e. Kelvin is required for this law
T1 = 30°C + 273K = 303K
T2 = 10°C + 273K = 283K
Using P1/T1 = P2/T2
30/303 = P2/283
Cross multiply
P2 × 303 = 30 × 283
303P2 = 8490
P2 = 8490/303
P2 = 28.02
New pressure of the gas = 28atm
The car's velocity after 5s : 10 m/s
<h3>Further explanation</h3>
Given
velocity=v=72 km/h=20 m/s
time=t = 5 s
acceleration=a = -2 m/s²
Required
velocity after 5s
Solution
Straight motion changes with constant acceleration

vf=final velocity
vi = initial velocity
Input the value :

The car is decelerating (acceleration is negative) so that its speed decreases
Longer than visable light
Answer: To show the number of atoms present.
Explanation: As in CO² (Carbon dioxide), there is a small 2 next to the symbol "O" (oxygen) to explain that there are two oxygen atoms.
The service rating of passengers car and commercial automotive motor oils