First, let's consider the Three of Wands in reverse. This card represents difficulties that can lead to a stalemate where nothing seems to happen. However, it can also indicate a new development in your friend's field of work, an opportunity that could be a starting point for new successes.

The King of Swords represents someone with some level of authority who is making important decisions for your friend. However, these decisions may not align with his aspirations and career ambitions. This could mean that your friend does not have control over the direction her career is taking her.

The Emperor reversed represents stonewalling and an inability to make progress towards goals. This could mean that the career opportunities your friend is working on won't materialize any time soon, even if there are some hurdles to overcome before that happens.

The Tower Reversed offers helpful advice to your friend: you need to shop around and explore more options, as there is no right or wrong way to achieve your goals. If your friend is stuck in one spot, she should reconsider her choices about her and think about ways to approach the situation differently.

In conclusion, from the four tarot cards we can deduce that your friend Sara's work situation is complex and has multiple facets that require further evaluations and insights. The cards suggest that your friend should be aware of new opportunities and consider all possible solutions to move forward in her career.