.The path of a celestial body or an artificial satellite as it revolves around another body due to their mutual gravitational <span>attraction.</span>
Answer:
Explanation:
Given
Each student exert a force of 
Let mass of car be m
there are 18 students who lifts the car
Total force by 18 students 
therefore weight of car 
mass of car 

(b)
17. a sea breeze is a breeze blowing towards the land
18. a land breeze is a breeze blowing towards the sea
Shear Stress= Force along the tangent/ Area
= 2700/π*r^2
=2700/3.14*16
=54