The answer is C (the same number of valence electrons)
Answer:

Explanation:
Time to mow 1 lawn by Wilma is 80 minutes
so work done in 1 minute by Wilma is given as
Similarly Rocky mow same lawn in 120 minute
so work done in 1 minute by Rocky is given as

now we know that they both worked by "t" time
so total work performed by them

they both mow 2 lawns then it is given as


Currently, many researchers are still working to find them.
Currently , its only theorized and they should be based on the quantum and particle theory
hope this helps
In 2 days there are 48 hours
to find the average speed per hour, divide 2,387 by 48
Which gets you the answer 49.72
Which rounds up to 50
The average speed is 50mph