Answer:
According to Utilitarianism, Jack should not take the job offered by his friend for the making of bio weapons. The reason is that utilitarianism believes in the ethics that will produce and work in the path of the greater good as product.
Whereas according to Kantianism, Jack should take the job because it is a work opportunity and focuses on the work rather than the outcome of it. If something is right, it is right regardless of how wrong the outcome might be.
The only difference between the two is that utilitarianism focus on greater end product whereas kantanism is opposite to it.