Update app.py

app.py

@@ -20,7 +20,7 @@ st.image(image, width=1000)
 
 #title
 st.title("Answering questions from scientific papers")
-st.markdown("##### This tool will allow you to ask questions and get answers based on scientific papers. It uses OpenAI's GPT models, and you must have your own API key. Each query is about 10k tokens, which costs about $0.20 on your own API key from OpenAI.")
+st.markdown("##### This tool will allow you to ask questions and get answers based on scientific papers. It uses OpenAI's GPT models, and you must have your own API key. Each query is about 10k tokens, which costs about only $0.20 on your own API key which is charged by OpenAI.")
 st.markdown("##### Current version searches on [ArXiv](https://arxiv.org) papers only. 🚧Under development🚧")
 st.markdown("Used libraries:\n * [PaperQA](https://github.com/whitead/paper-qa) \n* [langchain](https://github.com/hwchase17/langchain)")