Answer:
Answer:
3 g/cm
Explanation:
Mass of stone = 30 g
Initial volume of cylinder = 50 cm
Increased volume = 60 cm
Volume = 60-50
= 10 cm
Density of stone = Mass/Volume
= 30/10
= 3 g/ml as 1 ml = 1 cm
= 3 g/ml
Explanation:
Power = energy / time
Time should be in seconds
5 hours = 5 × 60 minutes = 5 × 60 ×60 seconds = 18000 s
Power = 6000/18000 = 0.333 W
Hope it helped!
To solve this problem we will apply the concepts related to centripetal acceleration, which will be the same - by balance - to the force of gravity on the body. To find this acceleration we must first find the orbital velocity through the Doppler formulas for the given periodic signals. In this way:

Here,
Orbital Velocity
Maximal Wavelength
Average Wavelength
c = Speed of light
Replacing with our values we have that,

<em>Note that the average signal is 3.000000m</em>

Now using the definition about centripetal acceleration we have,

Here,
v = Orbit Velocity
r = Radius of Orbit
Replacing with our values,



Applying Newton's equation for acceleration due to gravity,

Here,
G = Universal gravitational constant
M = Mass of the planet
r = Orbit
The acceleration due to gravity is the same as the previous centripetal acceleration by equilibrium, then rearranging to find the mass we have,



Therefore the mass of the planet is 
The ancient astronomers think areas of the moon called mares might be Seas.
Option D
<u>Explanation</u>:
The surface area of Earth's moon is dark, large, and is basaltic plains which are formed by ancient volcanic eruptions. They were dubbed as Maria, "ancient astronomers" who misunderstood them as actual seas. They are less reflective than highlands. Due to their iron-rich composition, they tend to appear dark from the naked eye. The Maria cover approximately about 16% of surface mostly on side that is visible from Earth. The few Maria on side that is too far are much smaller and residing mostly in very large craters. The ancient astronomers mistook the surface area as look like actual seas.