how long would you have to react to an object that is 20 m (65.6 feet) if you are traveling at 125 km/h (77.7 mph)

answer;

d. are made mostly of liquid

explanation;

-the general   composition and structure planets includes; they have a thick gas and liquid layer covering a small,solid core. mostly the gases are hydrogen and helium atmosphere and layers of liquid hydrogen. for instance neptune and uranus are examples of the outer planets, they have a core covered by ice and ammonia.

-neptune's atmosphere is hydrogen and helium with a bit of methane so there is no oxygen to breath and the interior is made up of frozen water and ammonia with a rock and iron core. thus, there is no liquid water or solid surface to survive.

98.4 m

explanation:

let s = distance up the plane  

then by conservation of energy  

1/2m(18.3)^2 = mg s sin(10)  

(18.3)^2 = 2g s sin(10)  

s = (18.3)^2/2gsin(10)  

= 98.39564526  

= 98.4 m