Answer: 30.641
Explanation: If you get the ave which is 38.0 then the vi which is 7.359
38.0-7.359=30.641/0.0 which is 30.641
Rock is completely immersed in hot water. By the second law of thermodynamics, thermal energy or heat is transferred from substance with higher temperature to substance with lower temperature until they come to thermal equilibrium i.e. both at same temperature.
It is given here that rock is at 20°C which is at lower temperature than water at 80°C. ∴Heat or thermal energy flows from water to rock. So, right choice is-
A. The water gives the rock thermal energy and gets no thermal energy in return.
Answer:
finding Cepheid variable and measuring their periods.
Explanation:
This method is called finding Cepheid variable and measuring their periods.
Cepheid variable is actually a type of star that has a radial pulsation having a varying brightness and diameter. This change in brightness is very well defined having a period and amplitude.
A potent clear link between the luminosity and pulsation period of a Cepheid variable developed Cepheids as an important determinants of cosmic criteria for scaling galactic and extra galactic distances. Henrietta Swan Leavitt revealed this robust feature of conventional Cepheid in 1908 after observing thousands of variable stars in the Magellanic Clouds. This in fact turn, by making comparisons its established luminosity to its measured brightness, allows one to evaluate the distance to the star.
As the number of significant figures increases, the more accurate or precise the measurement is.
<h3>What is significant figure?</h3>
The term significant figures refers to the number of important single digits in the coefficient of an expression in scientific notation.
Significant figures are the digits in a value that are known with some degree of confidence.
The effect of reporting more or fewer figures or digits than are significant;
As the number of significant figures increases, the more accurate or precise the measurement is.
As precision of a measurement increases, so does the number of significant figures.
Learn more about significant figures here: brainly.com/question/24491627
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