Answer: A
Explanation: STEP BY STEP
I think it's Barium sulfate, the soild and percipitate
Answer:
0.906
Explanation:
Let g = 9.81 m/s2. We can calculate the rate of change in potential energy when m = 201kg of water is falling down a distance of h = 131m per second

So the efficiency of the water turbine is the ratio of output power over input power:

A convergent meniscus lens is a lens that is composed of two spherical surfaces, like the on shown next:
The imaginary line that runs through the middle of the lens is the "symmetry axis".
In this type of lenses incident parallel beams of light converge in one point, as follows:
And thus we get the diagram.
Answer:
E3 = 3.03 10⁻¹⁶ kJ, E4 = 4.09 10⁻¹⁶ kJ and E5 = 4.58 10⁻¹⁶ kJ
Explanation:
They give us some spectral lines of the Balmer series, let's take the opportunity to place the values in SI units
n = 3 λ = 656.3 nm = 656.3 10⁻⁹ m
n = 4 λ = 486.1 nm = 486.1 10⁻⁹ m
n = 5 λ=434.0 nm = 434.0 10⁻⁹ m
Let's use the Planck equation
E = h f
The speed of light equation
c = λ f
replace
E = h c /λ
Where h is the Planck constant that is worth 6.63 10⁻³⁴ J s and c is the speed of light that is worth 3 10⁸ m / s
Let's calculate the energies
E = 6.63 10⁻³⁴ 3 10⁸ / λ
E = 19.89 10⁻²⁶ /λ
n = 3
E3 = 19.89 10⁻²⁶ / 656.3 10⁻⁹
E3 = 3.03 10⁻¹⁹ J
1 kJ = 10³ J
E3 = 3.03 10⁻¹⁶ kJ
n = 4
E4 = 19.89 10⁻²⁶ /486.1 10⁻⁹
E4 = 4.09 10⁻¹⁹ J
E4 = 4.09 10⁻¹⁶ kJ
n = 5
E5 = 19.89 10⁻²⁶ /434.0 10⁻⁹
E5 = 4.58 10⁻¹⁹ J
E5 = 4.58 10⁻¹⁶ kJ