Friend #1 gets at least 2/5 of a pizza.
Friend #2 gets at least 2/5 .
Friend #3 gets at least 2/5 .
Friend #4 gets at least 2/5 .
Friend #5 gets at least 2/5 .
Friend #6 gets at least 2/5 .
Sum . . . . . . . . . at least 12/5 of a pizza.
Simplify . . . . . . at least 2.4 pizzas.
-- If pizzas can be bought by the half, they should order at least <em>2-1/2 pizzas.</em>
-- If only whole pizzas have to be ordered, then they should order at least <em>3 pizzas.</em>
Answer:
The wave speed of the sound wave is 900
.
Explanation:
Wavelength is the minimum distance between two successive points on the wave that are in the same state of vibration. It is expressed in units of length (m).
Frequency is the number of vibrations that occur in a unit of time. Its unit is s⁻¹ or hertz (Hz).
The propagation velocity is the speed with which the wave propagates in the medium, that is, it is the magnitude that measures the speed at which the wave disturbance propagates along its displacement. Relate the wavelength (λ) and the frequency (f) inversely proportional using the following equation: v = f * λ.
In this case:
Replacing:
v= 500 Hz* 1.8 m
v= 900 
<u><em>The wave speed of the sound wave is 900 </em></u>
<u><em>.</em></u>
Evaporation is the process by which water changes from a liquid to a gas or vapor. Evaporation is the primary pathway that water moves from the liquid state back into the water cycle as atmospheric water vapor. Studies have shown that the oceans, seas, lakes, and rivers provide nearly 90 percent of the moisture in the atmosphere via evaporation, with the remaining 10 percent being contributed by plant transpiration.