Answer:
4 significant figures
Explanation:
Significant figures are the units/digits within a number that make the number more accurate and precise.
All digits (except for 0) are always significant. Therefore, all the digits in 43.55 are significant. Since there are 4 digits in the given number, there are 4 significant figures.
External
Stimuli are anything that causes arousal or enables an object to respond or react.
There are many different kinds of stimuli for which is different for every organism, for example, water, light and carbon dioxide are three stimuli and materials needed for photosynthesis in plants to manifest.
<span>In humans, we have nutrients or food, oxygen and water for us to survive. These are stimuli, eyes need light as a stimuli for it see and function. Nasal receptors needs smell as stimuli caused by molecular reactions of an object as a stimuli. And others. </span>
The final temperature of the mixture : 21.1° C
<h3>Further explanation </h3>
The law of conservation of energy can be applied to heat changes, i.e. the heat received / absorbed is the same as the heat released
Q in(gained) = Q out(lost)
Heat can be calculated using the formula:
Q = mc∆T
Q = heat, J
m = mass, g
c = specific heat, joules / g ° C
∆T = temperature difference, ° C / K
Q ethanol=Q water
mass ethanol=

mass water =

then the heat transfer :
