Answer:
The mass of Uranium present in a 1.2mg sample is 
Explanation:
The ration between Uranium mass and total sample mass is:
For a sample of mass 1.2 mg, the amount of uranium is:

Answer:
a. True
Explanation:
Solar radiation at frequencies of visible light passes through the atmosphere, heating the planet's surface, subsequently this energy is emitted in infrared thermal radiation. This radiation is absorbed by the gases produced by the combustion of fossil fuels. Therefore, the greater the amount of these gases in the atmosphere, the more heat will be trapped in the earth, raising its global temperature.
In cold winter day, the body temperature falls down from normal temperature of 98.6°F (37°C) to 95°F (35°C). In winter body losses heat faster than it generates heat. If the temperature fall further below 95°F (35°C), it is emergency condition known as Hypothermia. One has to consult doctor in this case.
In summer hot days, body evaporates water in the form of sweat, in order to remain itself cool. Rise of temperature up to 100°F is normal. It is recommended to hydrate body to maintain temperature in summer days.
Answer:

Explanation:
The moment of inertia of the system is equal to the each population and the platform inertia so
Inertia disk

Inertia person

Inertia dog

The Inertia of the system is the sum of each mass taking into account that all exert the force of inertia:


