Questions

Amazon, is an American electronic commerce and cloud computing company.

Payment gateways process credit card payments and other forms of internet transactions, in a secured format via any website or web-enabled device. They facilitate these transactions by transferring critical information between payment portals and the front-end processor, which is usually a bank.

Amazon uses its own payment gateway Amazon Pay Payment gateway.

Covalent bonds hold atoms together because the attraction between the positively charged nuclei and the negatively charged shared electrons is greater than the repulsions between the nuclei themselves.

The last line from the file "trial" would be read twice. To avoid this, ues:

       While ( fgets (str, 80, fp) ! = NULL)

               puts (str);