7kg of lead can safely be dissolved in 1000 kg of water.
<h3>What is ppm ?</h3>
It is a unit of measurement of concentration , also known as parts per million.
Amount of solute in 1 million parts of solution
1ppm = 1mg/kg
The maximum permitted level is 7ppm
This means 7mg /kg
For 1000 kg of water = 7000mg lead = 7kg of lead is permissible.
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Answer:
Step-by-step explanation:
cos a cos b+sin a sin b=cos (a-b)
cos 160 cos 10+sin 160 sin 10=cos (160-10)
=cos 150
=cos (180-30)
=-cos 30
=-√3/2
Answer: The value of both expressions when t=6 is 51, The value of both expressions when t=3 is 23,The two expressions are not equivalent.
Step-by-step explanation: i think thats it........but i might be wrong,,,,plz dont be mad if i am
The opposite of his number is positive.