What is the binary number 0010000100000000 in hexadecimal?

Answer 1

You need to count off four bits at a time, from the right (this is in case the number of binary digits is not an exact multiple of 4).

Then you replace each group of four binary digits by the hexadecimal equivalent. You can easily find a table of conversion online.

Answer 2

24.

You can easily do this yourself; split the binary number into 4 bit chunks:

0010 0100

The first chunk is 2, the second is 4.

Answer 3

A1