There is nothing conserved<span> in this reaction. When writing a β </span>equation<span>, remember that in the nucleus, a neutron ( n ) decays into a proton ( p+ ) and a high energy electron which is known as the beta ( β ) particle. Because a new proton has formed, the atomic number of the original atom will increase by 1</span>
Answer:- 0.134 seconds
Solution:- The speed is given as
and the circumference is 24900 miles which is same as the distance light have to covered. It asks to calculate the time required to cover this distance by the light.
We need to do unit conversion from miles to meter as the speed is given in meter per second.
1 mile = 1609.34 meter
So, 
= 40072566 meters
Know that, 
It's rearranged to time as, 
Let's plug in the values in it:

= 0.134 seconds
So, the light would take 0.134 seconds to travel the mentioned speed. The answer without the unit is 0.134.
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