Datatypes in C

Question

I'm working on a C# application right now. On this form, I have three fields. I'm not sure which datatype would be best for them. Some assistance will be greatly appreciated.

a: length of this field is 30 and it should be a positive integer
b: length of this field is 15 and it should be a decimal allowed positive number
c: length of this field is 15 and it should be a decimal allowed unsigned number

Also, what datatype should be used for the following:

a*b
a*c
b*c

Answer 1

You might be beginner I think. Go to this link https://docs.microsoft.com/en-us/previous-versions/visualstudio/visual-studio-2008/cs7y5x0x(v=vs.90)?redirectedfrom=MSDN

It is not that difficult to find out the answer