Final answer:
The task involves creating a program to count the number of characters in up to three user-entered sentences, using programming constructs such as for-loops, if-else, and while loops.
Step-by-step explanation:
This programming exercise pertains to string manipulation and basic control structures in computer programming. The student is asked to implement a solution where the program receives an input of up to three sentences and calculates the number of characters in each sentence, including whitespace. The problem requires knowledge of programming constructs such as for-loops, if-else statements, and while loops, and can be solved using any of these, based on the programmer's preference. An example solution using a while loop would involve asking the user for the number of sentences, checking that this number is between 0 and 3, and then reading each sentence, counting the characters, and printing the result. If 0 sentences are entered, the program will thank the user and exit.