Answer:
t = 2.2 s
Explanation:
Given that,
A person observes a firework display for A safe distance of 0.750 km.
d = 750 m
The speed of sound in air, v = 340 m/s
We need to find the between the person see and hear a firework explosion. let it is t. So, using the formula of speed.

So, the required time is 2.2 seconds.
Scott needs to determine the density of a metallic rod. First, he should determine the mass of his sample on the laboratory balance. Second, he should measure the volume of his sample by water displacement. Finally, he can calculate the density by dividing mass/volume.
Hope this helped ;)
Explanation:
내가 좋은 사람이 필요하고 내가 믿을 수 있는 사람이 필요하기 때문에 친구가 없다고 말하는 사람은 거의 없지만 대부분은 가짜이고 한국어를 모릅니다.
Particles become farther apart from each other in the change of state between liquid and gas.
Hope that helped =)
Saturn's rings are made of billions of pieces of ice, dust and rocks. Some of these particles are as small as a grain of salt, while others are as big as houses.