Heater is a compound b/c it is made out of atoms and b/c not all water has the same atoms
Answer: b. Salt lakes are formed when river bends are cut off.
Salt lakes are formed when water from water sourced gets accumulated in a shallow region and the supply of water is cut. These salt lakes are terminal which means water does not flow to other locations. Therefore, salt lakes are formed when river bends are cut off.
Answer:

Explanation:
Given data
Initial temperature of air Ti=300 K
Vf (final volume of air)=2Vi (initial volume of air )
To find
Final temperature
Solution
Since no energy is lost by thermal conduction during the process we categorize this process as an adiabatic one.Hence we apply;

Where air is predominantly a diatomic gas Y=1.4m
Substitute the given values
So

Answer:
The maximum wavelength of incident light that can produce photoelectrons from silver is 423.5 nm.
Explanation:
Given;
work function of silver, Φ = 2.93 eV = 2.93 x 1.602 x 10⁻¹⁹ J = 4.6939 x 10⁻¹⁹ J
Apply Einstein Photo electric effect;
E = K.E + Ф
Where;
E is the energy of the incident light
K.E is the kinetic of electron
Ф is the work function of silver surface
For the incident light to have maximum wavelength, the kinetic energy of the electron will be zero.
E = Ф
hf = Ф

where;
c is speed of light = 3 x 10⁸ m/s
h is Planck's constant, = 6.626 x 10⁻³⁴ J/s
λ is the wavelength of the incident light

Therefore, the maximum wavelength of incident light that can produce photoelectrons from silver is 423.5 nm.
Normal force, weight, Kinetic friction, and air resistance are a few I think of the top of my head.
I hope this helps