Answer:
Explanation:
Velocity at the bottom of height h
= √2gh
deceleration on rough horizontal surface
= μg , μ is coefficient of friction
= .27 x 9.8
= 2.646 m / s²
v² = u² - 2as
0 = 2gh - 2 x 2.646 x 19
h = 2 x 2.646 x 19 / 2 x 9.8
= 5.13 m
A:True because Lithium is the lighest solid and metal and the third lightest element.