Answer:
So combining blue with yellow light is like combining blue light with red and green light. The result of combining these three primary colors of light is to produce white light.
Explanation:
Data:
Q (Amount of heat) = 832 J
m (mass) = ?
c (Specific heat) = <span>0.90 J/(g × ° C)
T (final) = 97 ºC
To (initial) = 20 ºC
</span>ΔT = T - To → ΔT = 97 - 20 → ΔT = 77 ºC
Formula:
Q = m*c*ΔT
Solving:
Q = m*c*ΔT
832 = m*0.90*77
832 = 69.3m
69.3m = 832

So visualize soil mixed with water. To separate it, you can use a sieve to filter the water.
This is a simple algebraic problem, specifically for the mixture type of problem. Let x be the mass of 40% solution and y be the mass of 70% solution. The first equation would then be:
x + y = 20 --> eqn 1
The second equation would be the mass balance shown below:
(x)(0.40) + y(0.70) = 20(0.52) --> eqn 2
Rearranging eqn 1,
x = 20 - y
Substitute this to eqn 2:
(20 - y)(0.40) + y(0.70) = 20(0.52)
Solve for y,
y = 8 grams
Finally, solve for x.
x = 20 - 8 = 12 grams
<em>Therefore, Serena needs 12 grams of the 40% solution and 8 grams of the 70% solution.</em>