SOLUTION:
Step 1:
In this question, we are given the following:
In how many ways can the letters of the word STORAGE be arranged using only 4 letters at a time?
The details of the solution are as follows:
[tex]7\text{ P}_4\text{ = }\frac{7!}{(7-4)!}=\frac{7!}{3!}=\text{ 7x 6 x5 x 4 = 840 \lparen OPTION B \rparen}[/tex]CONCLUSION:
The final answer = 840 ( OPTION B )