Answer:
The required recursive formula is:

Step-by-step explanation:
We are given a geometric sequence as:
6,-18,54,-162,.....
Clearly after looking at different terms of the sequence we could observe that the sequence is an geometric progression (G.P.) with common ratio= -3 denoted by r.
Let
represents the nth term of the sequence.
This means that:

As the common ratio is -3.
so,

Hence, the required recursive formula for the geometric sequence is:

$96(2 payments) = $192
$192/(12 months) = $16 per month (she should set aside)
ANSWER

EXPLANATION
Since the parabola has the (0, 0) and the directrix at y=2.
The equation is of the form

where (h,k) is the vertex.
The vertex is half way between the directrix and the focus.
The vertex will be at (0,1)
and is the distance from the vertex to the focus which is 1.


You must factoring the number 192, you will get 192=2^6*3, so you have square root(2^6*3)=2^(6/2)*root(3) applying enhancing property.
Solve the exponent and you get =2^3*root(3)= 8*root(3)