D, electron, the nucleus is not a single particle to begin with, the proton has a positive charge, a neutron has a neutral charge or no charge, and an electron has a negative charge
        
             
        
        
        
Answer:
84.4 %
Explanation:
Mechanical efficiency = output work/input work × 100 %
 output work = 432 J of work for the bike to turn the gears
 input work = 512 J of work to ride.
Mechanical efficiency =  432 J/512 J × 100 % 
 = 0.844 × 100%
= 84.4 %
 
        
             
        
        
        
Answer:
 it needs to be shaken but make sure you have enough room to shake it safely
Explanation:
To properly operate the laboratory thermometer  it needs to be shaken but make sure you have enough room to shake it safely. This done because there is a small bend in the mercury channel of a clinical thermometer that uses mercury. You must shake the thermometer to get the mercury from a previous reading from the thermometer back into the bulb for taking new reading. The bend prevents flow back into the tube so that one can comfortably take reading.
 
        
             
        
        
        
Diagram D. shows the sound waves generated by a siren
that is moving with constant speed to the left.
A sound wave is the sample of disturbance caused by the movement of strength journeying thru a medium because it propagates far away from the supply of the sound. Sound waves are created by using object vibrations and bring strain waves, for example, a ringing cellular phone.
Sound waves fall into three classes: longitudinal waves, mechanical waves, and strain waves. keep studying to find out what qualifies them as such. Longitudinal Sound Waves A longitudinal wave is a wave wherein the movement of the medium's debris is parallel to the course of the energy transport. Sound propagates via air or different mediums as a longitudinal wave, in which the mechanical vibration constituting the wave occurs along the direction of propagation of the wave.
Learn more about sound waves here:-brainly.com/question/1199084
#SPJ9
 
        
             
        
        
        
Answer:
A. refraction of light waves
Explanation:
Refraction happens when light travels from one medium to another and changes speed and bends. This also causes objects to look different sizes and shapes when they are submerged in water.