use Java program pls.

29. Write a program, prompt to enter a string from the keyboard, and then display the length of the string and the first characters. I ) loop 19. In JAVA, no matter what the test conditions are, the following ( will be executed at least once. A for B. do..... while C. while D. while......do 17. How many lines of output will be produced by the following code fragment? for (int i = 0; i