Answer:
A
Explanation:
There are three basic forces in aerodynamics: acceleration, which moves an airplane forward; drag, which holds it back; and height, which keeps it airborne. Lift is generally explained by three theories: Bernoulli's principle, the Coanda effect, and Newton's third law of motion.
Answer:
Saturated zone is area below the water table in which the soil is completely saturated with groundwater.
Explanation:
The saturated zone lies below the ground. It is mainly the lower zone of rock along with the water table where pore spaces are completely filled with water. Even the saturated zone is sometimes separated into 2 subzones: the phreatic zone and the capillary fringe.
The area where pores spaces are not saturated with water is also unsaturated zone. Localized saturated zones can occur within the unsaturated zone. The unsaturated zone lies above the groundwater table.
Answer:
B
Explanation:
The whole thing is talking about the damage runoffs have done that is equal to answer B.
Answer:
finding Cepheid variable and measuring their periods.
Explanation:
This method is called finding Cepheid variable and measuring their periods.
Cepheid variable is actually a type of star that has a radial pulsation having a varying brightness and diameter. This change in brightness is very well defined having a period and amplitude.
A potent clear link between the luminosity and pulsation period of a Cepheid variable developed Cepheids as an important determinants of cosmic criteria for scaling galactic and extra galactic distances. Henrietta Swan Leavitt revealed this robust feature of conventional Cepheid in 1908 after observing thousands of variable stars in the Magellanic Clouds. This in fact turn, by making comparisons its established luminosity to its measured brightness, allows one to evaluate the distance to the star.
Answer:
0.002833 sec
Explanation:
Speed of light in vacuum is 
Given distance = 850 km = 850×1000=850000 m
We have to calculate the time that light take to travel the distance 850 km
Time 
So the time taken by light to travel 850 km is 0.002833 sec
