2. (10 points) Implement a function that computes binary string from an unsigned integer. For example f(15). The function returns NULL when it is not possible to compute the binary string. The function must have the following properties: (a) Name: DecimalToBinaryString (b) Return type: A string allocated in the heap (c) Argument1 Input: An unsigned integer. 3. (10 points) Implement a function that identifies unique words in a string. This function should be case insensitive, and words can be separated with multiple spaces. For instance, f(It makes sense. He Makes tea!")-It, makes, sense, He, tea!) The function must have the following properties: (a) Name: FindUniqueWords (b) Return type: An array of strings (i.e., char**) allocated in the heap. Return NULL if for some reason the function cannot operate on the input