Answer:
The second option
Explanation:
Speed is defined at the rate at which distance changes with time. It is scalar quantity and it is expressed as shown below:
Speed = 
At constant speed the rate of change of distance with time is the same. On the second graph, this is noticeable. Both distance and time change at the same rate.
Answer:
The activation energy of a chemical reaction is the energy that is required to be supplied for a chemical reaction to take place. The activation energy for the reaction of sodium is low compared to the energy released such that the reaction of sodium and water is spontaneous resulting in the melting of the sodium into liquid form
The activation energy of a candle wax is much higher, requiring the ignition of the wick which burns and in turn melts the candle wax to release vapors that burns alongside the wick to produce sooth carbon dioxide, carbon monoxide and water vapor and release of heat energy which also fuels further combustion of the candle wax and wick
Therefore, the activation energy of the candle wax and wick which require the heat of direct flame from an ignited matches is higher than the activation energy of sodium placed in a medium of water that reacts spontaneously without heat application
Explanation:
Qualitative because it changed its colour not its quantity :)
Answer:
It starts to become a red giant!
Explanation: