3. For added strength, many highways and buildings are constructed with reinforced concrete (concrete that is reinforced with embedded steel rods). The coefficient of linear expansion for concrete is the same as that for steel. Why is this important that these two coefficients be the same?

The answer is - It is important that the coefficients of steel and concrete to be the same because their rate of expansion is the same as the temperature increases therefore there is minimal problem with thermal stress.

Explanation:

The coefficient of linear for both concrete and steel are the same which is (12 x 10^-6). It is important that they both remain the same because when two different materials expand at the same rate then one will expand more than the other and it is very likely that one of them will break. If steel and concrete do not expand at the same rate then there would be faults such that the steel will push into the concrete and crack it or there would be gaps or weak spots where the steel did not expand therefore causing the building to collapse.

the economic difference between the three colonial regions. shipbuilding, whaling, fishing, and trapping where also main factors to the economy. the southern regional colonies economy was based on sugarcane, rice, cotton, tobacco, and indigo.