How do I know if address is in hex or dec?

Using Arduino Programming Questions
6

Thank you, it seems obvious now. If I had the register map below:

1254×478 33.9 KB

and I wanted to write FS_SEL=3 on register 0x16 then am I correct in saying:
FS_SEL =3 makes the line equal in binary:

00011000

which is equal to 24 in decimal, so i'd want:
writeTo(DEVICE, 0x16, 24); ?