One reason it was a health threat is it caused teeth to become ground down which would then lead to infections. The same was true with their eyes and lungs, sand would be blown into their eyes or inhaled into their lungs and then could cause infections.
One pretty straightforward answer could be investment to physical and human capital. But if you are if you are working with a mathematical model the answer to your question depends on the specific model. For example, in an equilibrium model from economic theory, you could find the determinants of labour productivity by taking the partial derivative of the production function with respect to the amount og labour.
A. Warmer ocean temp because a hurricane draws in warm air from bodies of water.
We are living social group. different kind of society and people
