Answer=4
A solution is a mixture of substances
True..........................................................
Answer:
<h3>Therefore, after long period of time 80kg of salt will remain in tank</h3>
Explanation:
given amount of salt at time t is A(t)
initial amount of salt =300 gm =0.3kg
=>A(0)=0.3
rate of salt inflow =5*0.4= 2 kg/min
rate of salt out flow =5*A/(200)=A/40
rate of change of salt at time t , dA/dt= rate of salt inflow- ratew of salt outflow

integrating factor

integrating factor 
multiply on both sides by 

integrate on both sides
b)
after long period of time means t - > ∞

<h3>Therefore, after long period of time 80kg of salt will remain in tank</h3>
Answer:
Failure is a lesson
Explanation:
Without failure, we'd be less capable of compassion, empathy, kindness, and great achievement. It's through failure that we learn the greatest lessons that life could teach us.
Answer: one molecule of O2.
Explanation: sweet i just took a guess but I believe that if 3 o2 molecules - 2 h2 molecules I think that its just basic maths and it is C because 3-2 = 1 and its o2 remaining, sorry if I’m wrong.