She needs to know the distance from LA to SF.
Call that distance x. Then you can calculate the cost from:
# of gallons consumed: x miles / 38 miles/ gallon = (x/38) gallons
After that,
cost = # gallons * cost per gallon = (x/38) gallons * 4 $/gallon = 4x/38 $
Answer is (4) - Pb.
According to the reactivity series of elements
- the elements which are above the hydrogen are more reactive than hydrogen.
- the elements which are below the hydrogen are less reactive than hydrogen.
Among the given choices, only Pb is placed above the hydrogen in the reactivity series and rest are below the hydrogen.
Hence, Pb is more active than hydrogen.
A p sub- level has 3 sub levels so it contains 6 electrons max
It is going through a physical change
