Answer:
1.38*10^18 kg
Explanation:
According to the Newton's law of universal gravitation:

where:
G= Gravitational constant (6.674×10−11 N · (m/kg)2)
ma= mass of the astronaut
mp= mass of the planet

so:

Answer:
Work done will be 2.205 j
Explanation:
We have given that the spring is compressed b 37.5 cm
So d = 0.375 m
Mass of the block m = 600 gram = 0.6 kg
Acceleration due to gravity 
Gravitational force on the block 
Now we know that work done is give by 
Answer:
Mixtures are materials that contain two or more chemical substances dispersed among each other (mixed together). If no chemical reaction occurs when two materials are mixed, they form a mixture. The chemical properties of the components don't change.
Explanation:
According to periodic trends in the periodic table, the atomic radius decreases from left to right.
In period three, the element with the smallest atomic radius would be the element in the rightmost area. Protons increase as it goes to the right, which would mean they pull in electrons closer which decreases the size.
So in period 3, the element with the smallest atomic radius is Argon (Ar).