Part a: Commas

Fortunately, Albert's determination has not been erased. He knows that yes, his work experience is of questionable value in the real world, but that won't stop him! The voice of his mother, who died recently, seems to be urging him forward: "Don't be pessimistic, Al. Whenever the going gets rough we have to put our noses to the grindstone!" That voice, its enthusiasm never waning, shields Albert from despair.

Part B: Semicolon

1) Driving in a rainstorm is always stressful; driving in a blizzard can be terrifying.

2) it was rainy and very chilly outside, but Marina decided to walk to work anyway.

3) in what seemed like a paradox to him, David was afraid of heights; however,...

Albert enters a pharmacy, noticing lots of customers in the aisles, but sees only one employee behind the counter. The employee looks frazzled; the customers look perturbed. Albert is reminded of Dr. Franz, a brilliant professor, and his graduate students. His hopes rise.