I tried my best for this I’m pretty for sure I remember doing this in school but I’m not for sure I hope this helped a little bit
Answer:

• subtract eqn(b) from eqn(a);

• find x :

124 - 78 = 46.....Harrison used 46 more blocks then Greyson
The answer is 5 because 5-2=3. S=5
A. Geometric
b. a curve sloping steeply upwards (exponential)
c. nth term an = a1r^(n-1)
nth term = 4(4)^(n-1)