Which is a complex sentence The technician installed my hard drive and turned on my computer. After you install the security software your computer will run smoothly. Both computers are powerful but t?

The complex sentence is "After you install the security software, your computer will run smoothly." This sentence contains an independent clause ("your computer will run smoothly") and a dependent clause ("After you install the security software"), which makes it complex. The other sentence about the technician is a compound sentence, and the last sentence is incomplete.