D. single- and simple multi-celled organisms
Although more complex animals like invertebrates and multi-celled organisms began to appear, it was very late compared to the original, simpler organisms for which the Precambrian time is characterized by.
Fractions have the / and decimals are the ones with the .
The U.S. has more than 87,000 dams greater than six feet high (and two million overall). While many dams continue to provide benefits such as flood control, irrigation, and water supply, for other dams the cost of maintenance or the negative effects on communities, fish, and tribes justifies their removal.
Dam owners and regulators decide whether to remove a dam by weighing many factors including: the cost of removal and the ability to replace any lost power generation against avoided long-term maintenance; safety concerns; benefits to endangered fish populations; increased recreational and commercial fishing; and restoration of cultural values of nearby tribes.
By 2020, roughly 70% of dams will be more than 50 years old, inviting us to reconsider the value to the public of long-term investments in this infrastructure.
Answer: life expectancy
Explanation: By January of 1992, by popular demand, theSoviet Union ceased to exist. In its place, a new entity was formed. It was called the “Commonwealth of Independent Republics,” and was composed of most of the independent countries of the former Soviet Union.After the fall of communism in russia, all of the following increased except life expectancy
There is a close relationship between evaporation( transformation of water into water vapor in presence of heat), condensation (transformation of water vapor into water droplets), condensation nuclei (minute water droplet) and cloud (assemblage of too many water droplets). For the formation of cloud all these mentioned conditions are required.
Explanation:
Evaporation refers to the transformation of water into water vapor by the action of heat, condensation means transformation of water vapor into water droplet in normal temperature, condensation nuclei refers to the water droplets which is base of formation of cloud.
Cloud forms from the assemblage of water droplets. These water droplets are formed in saturated air condition when the air is full of humidity. Relative humidity means the ratio between the water holding capacity of air and the amount of actual water in air at that particular temperature.