Answer:
a.
f(1)=6; f(n)=6+d(n-1), n>0
Explanation:
We are given that
First layer has squares, a=6
Second layer has squares, a2=12
We have to find an arithmetic explicit formula to determine the number of squares in each layer.
nth term of an A.P
Substitute the value of a
Now, we get
f(1)=a=6
Hence, option a is correct.
a.
f(1)=6; f(n)=6+d(n-1), n>0