4 is again c because you should put the 2 here 2a'2-1 so this is 2a'1 and this is 20 so
A2 is 20
Than you should again do this and find a3 ...
Answer:
umm i think it is 5 cm but im not sure
Answer:
first get their difference and then get positions of the difference and get the factors and then you will get the nth term
