How many cubes or in this tower?

What is the sum of the first 8 terms of the geometric series

Someone answer this asap for gabriella uses the current exchange rate to write the function, h(x), where x is the number of u.s. dollars and h(x) is the number of euros, the european union currency. she checks the rate and finds that h(100) = 7.5. which statement best describes what h(100) = 75 signifies? a. gabriella averages 7.5 u.s. dollars for every 100 euros. b. gabriella averages 100 u.s. dollars for every 25 euros. c. gabriella can exchange 75 u.s. dollars for 100 euros. d. gabriella can exchange 100 u.s. dollars for 75 euros.

The nth term of a sequence in 2n-1 the nth term of a different sequence is 3n+1 work out 3 numbers that are in bothe sequences and are between 20 and 40