76.88 I think im sorry if wrong
A contact force is a force in which and object comes in contact with a another object. A non-contact force, is a force is an object applied by another body. (A good example of a non-contact force is gravity)
Hertz is units for frequency. (waves per second)
wavelength = speed/frequency
if you're given the speed use that to calculate, if not then you can probably assume it's a wave of light and use the speed of light (3x10^8 m/s) to calculate.
wavelength = (3x10^8)/(1.28x10^17)
= 0.000000002 m
= 2.34 nm
The Law of Conservation of Mass dates from Antoine Lavoisier's 1789 discovery that mass is neither created nor destroyed in chemical reactions. ... If we account for all reactants and products in a chemical reaction, the total mass will be the same at any point in time in any closed system.
Saturated hydrocarbons consists of C-C single bond whereas Unsaturated hydrocarbons consists C-C double/triple bond.