Answer:   21, 63
<u>Step-by-step explanation:</u>
We need to find two geometric means between 7 and 189.
The Geometric Sequence is: 7, ____, ____, 189
Let's find r (common ratio): 
We can see that the common ratio will be multiplied by itsely 3 times in order to get from 7 to 189:
                                            7 r³ = 189
                                             
                                             r³ = 27
                                           ∛r³ = ∛27
                                               r = 3
Now that we know the common ratio is 3, we can multiply 7 and 3 to get the next term (21), and multiply that by 3 to get the third term (63), and multiply that by 3 as a check to confirm we get 189. 
7 x 3 = 21
            21 x 3 = 63
                          63 x 3 = 189  
 
The completed Geometric Sequence is: 7, <u>21</u>,  <u>63</u>, 189