Answer:
37.545 m/s
Explanation:
f' = Actual frequency of horn = 269 Hz
f = Observed frequency of horn = 290 Hz
v = Speed of sound in air = 343 m/s
= Speed of second train = 13.7 m/s
= Speed of first train
From Doppler effect we have

The speed of the first train is 37.545 m/s
The heat required to raise the temperature of the unit mass of a given substance by a given amount (usually one degree).
or C. Mass if you're on plato
Answer:
The ability of our bodies to adapt to different levels of gravity. You would become weaker and your heart is use to zero gravity. Boredom because there isn't much to in space. When intelligent people get bored, it's not pretty all the time...
Density is the mass per unit volume of any object. It is calculated by dividing the mass of an object by its volume. This is:
ρ = m/V
ρ = 4.05 g / 12 mL
ρ = 0.3375 g/mL
<h3>
ρ ≅ 0.338 g/mL</h3>
OPTION A
Answer:
Albert Einstein
Explanation:
He first predicted the existence of black holes in 1916