I think its all four of them could be wrong but try all four !!!!!!
Answer:
The correct answer is "4.26 m".
Explanation:
Given:
Wavelength,

or,

Distance,

or,

Distance between the 1st and 2nd dark fringes,
As we know,
⇒ 
or,
⇒ 
By substituting the values, we get




Answer:
7 hours
Explanation:
The total charge contained in the battery is

And this is a charge, since it is a current multiplied by a time:

The current drawn by each headlight (which is the charge consumed per second) is

Since we have two headlight, the total current drawn is

Therefore, the total charge consumed by the two headlights each hour is

So, the time before the battery is dead is

The answer to this would be :
<span>consequence
</span>hope that this helps you!
Source: I had done a research about this. =)