Answer:
137.2J
Explanation:
Ep= mgh
Given,
and we know, g = 9.81 N/kg
Ep= 2 × 9.81 × 7
Ep= 137.2J
Answer: Kinetic frictional force = 23.76N
Explanation: Please see the attachments below
green liquid becoming a red liquid
Answer:
The velocity is 
Henrietta is at distance
from the under the window
Explanation:
From the question we are told that
The speed of Henrietta is 
The height of the window from the ground is 
Generally the time taken for the lunch to reach the ground assuming it fell directly under the window is

=>
=>
Generally the time taken for the lunch to reach Henrietta is mathematically represented as

Here
is the time duration that elapsed after Henrietta has passed below the window the value is given as 4 s
Now
=>
Generally the distance covered by Henrietta before catching her lunch is

=> 
=> 
Generally the speed with which Bruce threw her lunch is mathematically represented as


<span>Solar panels convert light energy from sunlight into electricity energy , Metalloid is most likely used in solar panels The answer is : </span> A metalloid is used because it is a semiconductor and can become more conductive when more light shines on it. Metalloids are shiny,<span> semiconductive and they are brittle.</span>