Sometimes I question if I’m being stupid

I’m new to the call center customer service field and there are times that I question the whole “there’s no stupid questions” thing. I work for a company that manufactures products and our customers are the distributers. Most calls are the typical checking on orders, getting quotes, password change, people thinking they are special and demand unrealistic things etc, but there are a few that make it hard for me to keep my composure. Call #1: Distributer (D) calls because her customer asked her about the quantity of items in the box that was delivered to her. She’s telling me only one box arrived. I check the order and the shipping details and this item is shipped 500 per box so I tell D that is why her customer only received one box. Then she says “Are you sure there are 500 in the box? My customer is asking how many are in the box.” I tell her again how they are shipped and then I ask if the customer opened the box and looked? She says she doesn’t know the customer just texted her and asked… so I’m thinking why did she just open the box? The item she ordered is small so what did she think we were going to send 500 mini boxes? Me and D had a laugh about it. #2: Distributer calls inquiring about a table cloth. In the description it says backside is white. She tells me her customer wants it printed on both sides. After extensive explaining she didn’t understand that the back side was the part that touches the table and no one will see it. #3 Distributer calls asking for a stainless steel cup. I give her two options one shiny like a mirror and matte. She informs me that she ordered both options but her customer wants it “stainless steel” colored. The cups come in multiple colors, silver being one, which means they don’t put anything on it to change the color. So I tell her both come in silver. She tells me again they don’t want silver they want stainless steel color. This goes on for 10 minutes. I finally put her on hold and ask my manager to make sure I’m not crazy. I end up telling her we only carry the silver. Am I dumb? What color is stainless steel? #4: Distributer calls wants the diameter of the opening of a straw. I burst out laughing, he also thought it was funny. Had to call another department so they could measure for me and I could barely get the words out I felt so ridiculous asking.