Question

why are there increasing problems with construction in permafrost regions?
the existence of black spruce trees
global cooling
booming arctic populations
longer freeze - thaw cycles
question 29
0.4 pts
how do students make a choice about which schools to attend in russia?
students are assigned based on neighborhood.
students are assigned based on area of interest.
students are assigned based on exam scores.
students may choose any school they would like to attend.

Explanation:

First Question (About construction in permafrost regions)

To determine why construction problems increase in permafrost regions, we analyze each option:

• "The existence of black spruce trees" is irrelevant to construction problems in permafrost.
• "Global cooling" would not increase problems; in fact, warming is a concern.
• "Booming arctic populations" is not a direct cause of construction problems related to permafrost's physical properties.
• "Longer freeze - thaw cycles" occur due to climate change (warming trends). As permafrost thaws and refreezes more, the ground's stability is affected, leading to issues like ground settlement, which impacts construction. So this is the correct reason.

To determine how students choose schools in Russia:

• "Students are assigned based on neighborhood" is a common model in some regions, but in Russia, school assignment for general education (especially in the context of the question's options) is often neighborhood - based for basic schooling.
• "Students are assigned based on area of interest" is more relevant for higher education or specialized schools later, not the general school choice context here.
• "Students are assigned based on exam scores" is more for competitive or specialized admissions, not the primary way for general school attendance.
• "Students may choose any school they would like to attend" is not accurate as there are usually zoning or assignment rules. So the correct option is that students are assigned based on neighborhood.

Answer:

Longer freeze - thaw cycles

Second Question (About school choice in Russia)