Instruction: Answer the given question by extracting information from the supporting document.

Input:
Question: How many heating elements inside total?
Document: Included is also a photo of the oven while on. You can see the heating elements and what I like is that they are protected by a metal "shroud" not just on the area where food might spatter on them, but also on the other side which means they are fully protected if something does spill - it will not spill on the heating element so clean up will be easy.5. Several reviews have mentioned that the temperatures and times are hard to read on the knobs.
So loud. It hums really loudly when first powered on, as the elements heat up, plus lots of ticking of expanding metal, and the hum fades somewhat, but it's always there. My old oven was never that loud.
The roll up cover gives me more space on the counter top. It heats quickly, but the timer dial is hard to read. Perhaps a black line where the bump is would help. The inside is smaller than my previous toaster oven.
I like the design of this product. It gives an ample room to manage the item inside of the oven and I don't have to worry too much about getting thermal injuries. It is rather small in capacity but accommodate a small size of pizza.
And that matters, because the toaster turns itself off when it builds up more heat inside than it wants. So that interrupts the broiling process. I have found ways to sort of get around this, but I really wish it had a true broil setting -- top burner on, bottom burner off.
When I opened the product and got it out of its packaging, I noticed it felt a little dusty.I swiped my finger across the top and looked to see how dusty my finger was, and I was shocked to see metal flakes all over.Testing the inside, I got the same result.
Am really afraid to ever use this again to broil. Both elements stay on. Why in the world would you need a bottom element ON when the bottom of the broiler pan keeps anything from broiling on the bottom? I did two burgers once, never again. Took over 30 minutes to get them broiled since the oven gets so hot it keeps turning off. I wouldn't recommend it to anyone. This was twice the price of my previous oven.
The tops were burnt and the inside was gooey.&#10008; The exterior of the unit gets very, very hot. Hot enough to burn skin.&#10008; After closing the roll top cover a tight seal is not formed between the closed roll top cover and the main body of the unit. When closed there are several visible gaps between top and the rest of the unit.
I really like the easy-to-raise door -- makes the inside more accessible. But there is one thing I don't like. When you &#34;broil&#34; something, you are using high, top heat only. So on a broil setting, the top burner should be on but not the bottom burner. There is apparently no setting for that. Toasting (two-sided) and broiling are exactly the same function.
The specs were also on the top, and if I hadn't cleaned it, swinging the door over and over across the top could move some of that dust down into whatever is being toasted.It wouldn't be a big deal, but this is supposed to handle food and we shouldn't have to put it through the car wash to clean it from metal debris.Sorry, guys, but metal shavings covering the inside and out of a food handling product = 1 star.
Answer: Two.  There is one on the top and one on the bottom.