T_n = 3 * T_(n-1)
Long way (always works!)
T_5 = 3*T_4,
T_4 = 3*T_3
T_3 = 3*T_2
T_2 = 3*T_1
T_5 = 3*3*3*3*T_1 = 81*T_1 = 81*8 = 648!
Short way (sometimes it works!)
T_n = 3^(n-1) * T_1 (this case is a geometric series of ratio-=3)
T_5 = 3^4*8 = 648
EF = 50 in.
In similar figures, corresponding sides are proportional. We use the similarity statement ABCD~EFGH to write a proportion:

Cross multiply the proportion:
45*x = 75*30
45x = 2250
Divide both sides by 45:
45x/45 = 2250/45
x = 50
Answer:
The third one.
Step-by-step explanation: