Ques & Ans: Context: Herbert S. Zim, in his classic introductory cryptography text "Codes and Secret Writing", gives the English letter frequency sequence as "ETAON RISHD LFCMU GYPWB VKJXQ Z", the most common letter pairs as "TH HE AN RE ER IN ON AT ND ST ES EN OF TE ED OR TI HI AS TO", and the most common doubled letters as "LL EE SS OO TT FF RR NN PP CC".

Question: letters of the alphabet in order of usage?
ETAON RISHD LFCMU GYPWB VKJXQ Z

Stream of consciousness: The relevant sentence in the passage is: Herbert S. Zim, in his classic introductory cryptography text "Codes and Secret Writing", gives the English letter frequency sequence as "ETAON RISHD LFCMU GYPWB VKJXQ Z", the most common letter pairs as "TH HE AN RE ER IN ON AT ND ST ES EN OF TE ED OR TI HI AS TO", and the most common doubled letters as "LL EE SS OO TT FF RR NN PP CC".

Ques & Ans: Although the work is not gnostic in a theological sense, the author, who considers himself to be a teacher to the unidentified audience to which he writes (see e.g. 9.9), intends to impart to his readers the perfect gnosis (knowledge), that they may perceive that the Christians are the only true covenant people, and that the Jewish people are no longer in covenant with God (3.7). His polemics are, above all, directed against Judaizing Christians (see Ebionites, Nazarenes, Judaizing teachers).

Based on this passage, what is the main message of the epistle of barnabas?
the perfect gnosis ( knowledge ) , that they may perceive that the Christians are the only true covenant people , and that the Jewish people are no longer in covenant with God ( 3.7 )

Stream of consciousness: To answer this question, we should know that: Although the work is not gnostic in a theological sense, the author, who considers himself to be a teacher to the unidentified audience to which he writes (see e.g. 9.9), intends to impart to his readers the perfect gnosis (knowledge), that they may perceive that the Christians are the only true covenant people, and that the Jewish people are no longer in covenant with God (3.7).

Ques & Ans: Emilie du Chatelet (1706 -- 1749) proposed and tested the hypothesis of the conservation of total energy, as distinct from momentum. Inspired by the theories of Gottfried Leibniz, she repeated and publicized an experiment originally devised by Willem' s Gravesande in 1722 in which balls were dropped from different heights into a sheet of soft clay. Each ball's kinetic energy-as indicated by the quantity of material displaced-was shown to be proportional to the square of the velocity. The deformation of the clay was found to be directly proportional to the height the balls were dropped from, equal to the initial potential energy. Earlier workers, including Newton and Voltaire, had all believed that "energy" (so far as they understood the concept at all) was not distinct from momentum and therefore proportional to velocity. According to this understanding, the deformation of the clay should have been proportional to the square root of the height from which the balls were dropped from. In classical physics the correct formula is E k = 1 2 m v 2 (\ displaystyle E_ ( k) = (\ frac ( 1) (2) ) mv ^ (2) ), where E k (\ displaystyle E_ ( k) ) is the kinetic energy of an object, m (\ displaystyle m) its mass and v (\ displaystyle v) its speed. On this basis, Chatelet proposed that energy must always have the same dimensions in any form, which is necessary to be able to relate it in different forms (kinetic, potential, heat ...).

Who made the law of conservation of energy?
Emilie du Chatelet

Stream of consciousness:
To answer the question, consider the following: Emilie du Chatelet (1706 -- 1749) proposed and tested the hypothesis of the conservation of total energy, as distinct from momentum.