SOLUTION
Given the question, the following are the solution steps to answer the question.
STEP 1: Decide the formula to use
Since it can be seen from the question that order is important, we use the Permutation approach which is given by the formula:

STEP 2: Find the number of possible ways
![\begin{gathered} n=7,r=1\left(opening\right)+1\left(middle\right)+1\left(ending\right)=3 \\ we\text{ have;} \\ ^7P_3=(7!)/(\left(7-3\right)!)=(7!)/(4!)=(7*6*5*4!)/(4!)=7*6*5=210 \end{gathered}]()
Hence, there are 210 possible ways