Answer: A
Explanation: isotopes of the same thing element have the same number of protons in the nucleus but differ in the number of neutrons.
Answer:

Explanation:
Given that,
Lightning flashes one mile (1609 m) away from you.
We need to find the time it take the light to travel that distance. Let the time be t. We know that,
speed = distance/time

So, the required time is 
Answer:
$900 trillion
Explanation:
If Alaska is 20% of the contiguous US, then the approximate area of interest is ...
1200 miles × 3000 miles = 3.6×10^6 square miles.
The size of a dollar bill is about ...
(6.5 cm)·(15.5 cm) = 100.75 cm^2
One mile is 160,934.4 cm, so 1 square mile is about ...
1 mi^2 = (160,934.4 cm)^2 ≈ 2.59·10^10 cm^2
The number of dollars of interest is then ...
(3.6 · 10^6 mi^2)(2.59 · 10^10 cm^2)/(100.75 cm^2) ≈ 9.3·10^14
≈ 930 × 10^12 . . . dollars
It would cost about 900 trillion dollars to cover the land area of the US in $1 bills.
inverted, real, behind the lens is the answer
light and radiation is able to experience by an observer watching the explosion from the vacuum.
<u>Explanation:</u>
- Basically in the nuclear explosion, there will be an enormous of energy released as noise, heat, visible light, radiation and atmospheric wave.
- Usually sound and wave propagate through medium but in vacuum, there will be no medium to transfer this type of energy. so there is no chance of sound and wave transfer.
- Light and radiation travel in vacuum because they didn't need the medium to transfer .