Military personnel also use periscopes in some gun turrets and in armoured vehicles. More complex periscopes using prisms or advanced fibre optics instead of mirrors and providing magnification operate on submarines and in various fields of science
Your answer is C) The speed of sound is higher in solids than in liquids.
A conservative force is a force that when work is done against this force the work done does not depend on the path taken only the initial and final position.
Answer:

Explanation:Newton.s law of cooling states that the rate of cooling of an object is proportional to the difference between its own temperatures and temperature of its surroundings. Mathematically,
![\frac{dQ}{dt} =-hA [T(t)-T(s)]\\](https://tex.z-dn.net/?f=%5Cfrac%7BdQ%7D%7Bdt%7D%20%3D-hA%20%5BT%28t%29-T%28s%29%5D%5C%5C)

where
is the heat transfer
is heat transfer coefficient
is the heat transfer surface area
is the temperature of the object's surface
is the temperature of the surroundings