Final answer:
The lever responsible for creating spaces and for returning the carriage to the beginning of the line on a typewriter is the line space lever.
Step-by-step explanation:
The lever used for making spaces and for returning the carriage in the right direction on a typewriter is known as the line space lever. When you want to start a new line of text, you would press down this lever, which would both advance the paper by one line and move the carriage back to the starting (leftmost) position. This allows you to continue typing without any interruption. The lever performs two functions: it moves the carriage (a) from right to left and it advances the paper (b) upwards, making room for the new line of text.