جواب / إجابة
Answer: something that you say or write when someone has asked you a question
The answer to your question is yes
رد / جواب
Reply: an answer, especially to a letter or telephone call
We wrote last week, but haven’t had a reply yet
We had six replies to our advertisement
استجابة / رد فعل / جواب
Response: something that you do or say as a reaction to something
There was no response to our call for help
The changes produced an angry response from customers
خطاب (يشعر) بالإستلام / خطاب شكر
Acknowledgement: a letter or note sent to say that something has been received
We didn’t even receive an acknowledgement from the council
She received a letter of acknowledgement
أخيكم / سيد إسماعيل