Instruction: Given a question and the related document, predict if the question is answerable based on the information provided in the document. Output only yes or no.

Input:
Question: Does anybody know if you can use tennis balls?
Document: My son is so happy. Every evening he play at the yard with the Pitching Machine. The only concern is about the plastic balls. He lost 6 and I don't know here to buy it.Thanks,Mercy
Regular Wiffle balls also work but will sometimes curve. The machine shoots balls relatively fast and straight. I use it in-doors from a distance of 25 feet. For $40 this is a terrific machine. I'd highly recommend this to anyone looking for an inexpensive way to take batting practice.
I realize that this is an inexpensive little pitching machine, and you do get what you pay for. However, this is just bad bad bad. My son moved up from tee ball to machine pitch this year so I bought this so he could get in extra practice at home. He has spent more time picking up balls from my endless attempts at adjusting it than actually using it. This thing is so inconsistent, its completely impossible to use.
Bought this for my 9 year old grandson and was afraid that it wouldn't work well enough for him and his 8 year old brother to use. I haven't had very good luck with toys lately and I thought a pitching machine for $29 was asking a lot. However, it worked just fine. I had purchased an extra set of balls so there would be enough for two rounds before the gathering up process.
I would call this more a sporting machine than a toy. My purpose was to use this to practice batting (baseball/softball) and for my kids to practice aswell. The balls FIRE (really shoot fast) out of this machine. This is really good to practice your reflexes and alittle to fast for my 6 and 8 year old to bat off. The balls that come with this are softer than the balls you can purchase as extra's and they also shoot the ball distance differently.
I bought this for my seven year old for soft toss batting practice. It's to inconsistent to use as batting practice in any fashion. One pitch will be right down the middle, the next will go behind his back and the next will be 10 feet outside. It's good if you want to practice catching line drives or short fly balls. That's it. I am going to bite the bullet and purchase a real pitching machine. Also we went through 8 "D" batteries in less than an hour.
I purchased this for a little boy turning 3. I know it's for children older but this is a kid who is very sports minded! First word "ball". He loves it! He doesn't hit every pitch but his gross motor skills are excellent and getting better all the time! Glad it was  out there and an option.
I haven't found anything better than this, but I would not use it as a toy and only supervised with small children. I have already recommended this to a friend for her kids to practice catching off.
My son is 4 and already hitting them out of the park with this pitching machine. Loads of fun for the whole family. Have it set on a level surface in the back yard. I use a patio 12x12 tile.
Very first pitch was a little high, but in the strike zone. Second pitch went completely behind the batter. It only got worse from there. I've tried three different times to use it, same results every time. I wish I had saved my money.
Answer: yes