A 70.-kg person exposed to ⁹⁰Sr absorbs 6.0X10⁵ β⁻ particles, each with an energy of 8.74X10⁻¹⁴ J.
<h3>What is β⁻ particles ?</h3>
A beta particle, also known as a beta ray or beta radiation (symbol ), is a highly energetic, swiftly moving electron or positron that is released during the radioactive disintegration of an atomic nucleus. Beta decay occurs in two ways: decay and + decay, which result in the production of electrons and positrons, respectively.
In air, beta particles with an energy of 0.5 MeV have a range of roughly one meter; the range is energy-dependent.
Ionizing radiation of the sort known as beta particles is regarded, for the purposes of radiation protection, as being more ionizing than gamma rays but less ionizing than alpha particles. The damage to live tissue increases as the ionizing effect increases, but so does the radiation's penetration power.
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Answer:

Explanation:
= First mass of water = 12 oz
= Second mass of water = 20 oz
= Temperature difference of the solution with respect to the first mass of water =
= Temperature difference of the solution with respect to the second mass of water = 
c = Specific heat of water
As heat gain and loss in the system is equal we have

The final temperature of the solution is
.
Explanation:
this is a process were by water vapour goes up to the atmosphere and cool which makes cloud's. then water vapour begins to accumulate and when the clouds are heavy then they pour down rain etc
When there is a transfer of heat a wind usually blows from where the heat is transferred from