Orthodontic problems such as crowding and malocclusions are widespread in humans today, but the study of ancient skulls tells us that this was rare before 10,000 years ago. what factors explain this observation?

Today humans suffer more from orthodontic issues compared to ancient humans because of the change of food from hard foods to soft foods. This resulted to smaller faces and smaller jaws together with rounder and shorter cranial vault. This made the bones supporting the teeth reduce in size faster than the teeth resulting to crowding and malocclusions.

Nimbostratus is the correct answer.
explanation: nimbostratus clouds are the type of clouds that are mostly likely present on gray, rainy day. these clouds produce continuous rain, snow and there is no thundering or lightening either.

The short-term effect of tar on the body is increased blood pressure.