Robotic Engineers at NASA added a set of scientific tools to the Perseverance. Name two:

Laser, rock/dirt sample drill thing. That drops little packets of the samples for collection later

Explanation:

john maynard keynes developed new economic theories in response to the : b) great depression of the 1930s. his theories are so important that they are known as "keynesianism". in his works he supports the idea of a government with deeper involvement and intervention to end the great depression.