You should go straight to the source to learn how to make lots more sense of these clues.
Short hit, in sports
Preposition
Character in the Hardy Boys series
One word in PIN (abbr.)
Certain person in a multiple birth, casually
"I'm so disappointed in you!" sound
Moving vehicle
Certain science classroom, casually (2 wds.)
Rapper
14th-century Russian ruler (2 wds.)
Certain Paralympic equipment pieces (2 wds.)
Tries to get a closer look, maybe
Mobile ripoff with the tagline "Who Is The Impostor" (2 wds.)
Operating system
4
1
5
2
2
3
4
6
3
5