A(n) = a₁.(r)ⁿ⁻¹, where a₁ = 1st term, r= common ratio and n, the rank
In the formula given a₁ = 5, r = 3/2 and n = 6 (we have to find the 6th term value).
a₆ = 5.(3/2)⁶⁻¹ = 5.(3/2)⁵ = 1215/32 (answer C)
1500 total surveys sent
Returned: 245 + 173 + 185 + 92 = 695
1500-695 = 805
Answer: A, 4^4
Step-by-step explanation:
4^7/4^3 = 4^4
In both cases,

(as a consequence of the interesecting secant-tangent theorem)
So we have
10.





(omit the negative solution because that would make at least one of AB or AD have negative length)
11.




(again, omit the solutions that would give a negative length for either AB or AD)