(1) Covert a Hexadecimal to decimal (there is a video for you to watch too). Then write a program that can convert a binary to decimal (only for integer case).

a) Directly use Java built-in method to do this. In this case, only couple lines of code. Hint: Study Integer class in Java.

b) Write your own code to convert a binary to decimal from scratch. The input is a binary string. The program output is its corresponding decimal value. This way you need to design the algorithm.