Based on the code segment below and by using cstring and/or cctype functions, write C++ statements to perform each of the following instructions. Note that, each question is dependent. Important: Please write C ++ statements WITHOUT blank spaces unless it is absolutely needed. Example: int num, a,b; char d1[10] "disease"; char d2[10] = "autism"; char d3[15]; int len; 1 2 4 a) Concatenates dl string to the end of d2 string. b) Copy the resulting string in (a) into d3 . c) Store the length of d3 into len. d) Converts d3 string to uppercase by filling in the blanks in the code segment below with an appropriate statement. d) Converts d3 string to uppercase by filling in the blanks in the code segment below with an appropriate statement. for (int x = 0; ;x++)