Answer:
D ko alam pasensya ka na ha
If you stand up in a big room and echo, your voice will echo
from the walls. As long as the room is empty. Since
the speed of sound is constant, depending on air density, the more humid the
air the faster and farther sound travels. The
speed of sound is constant, you could measure the time it takes for your voice
to echo off the walls. The same thing happens with Doppler radar, but it’s not voice,
it has higher frequency signals.<span> </span>
I believe it is positive.
Answer:
Explanation:
Given
winning car accelerates with a and its final velocity is v
considering they both start from rest
time taken by winning car is
v=u+at
where u=initial velocity
a=acceleration
t=time


Now loosing car is accelerating with 
Distance traveled by loosing car in time t



Thus distance d traveled by loosing car is given by 
Answer:
i can't click the answer bottom but the answer is "17th to 18th century" i hope this helps