<span> A pure substance is an material which contains atoms of only one kind.
It has fixed physical and chemical properties such as boiling point, melting point, valency, density and more.</span>
Answer:
Adaptive radiation usually refers to the diversification of living species that are evolved from a common ancestor. There occur changes and modifications in the ecological system, due to which the species can adapt to the changing environment with the available resources. It also modifies the ways in which the existing species interacts with the surrounding environment. Here, the species select the ecological niches naturally.
A plant named 'silver sword' that is commonly found in Hawaii, and the appearance and diversification of mammals after the extinction of dinosaurs by the end of Cretaceous, are two examples of adaptive radiation.
High pH is a very basic, alkaline solution. It will feel slippery/slimmy and reacts with metals to produce hydrogen gas.
Answer:
Thickness is 0.086 ft
Solution:
iAs per the question:
Temperature, T = 
Energy to be stored, E = 150000 Btu
Area of the concrete floor, A = 
Density of concrete, 
The heat energy is given by:
(1)
Also, we know that:
1 Btu = 1055 J



where
= density
m = Mass
V = Volume
A = Area
t = thickness
s = 750 Jk/kg
Now, eqn (1) can be written as:

Thickness can be written as:


t = 0.02625 m
t = 
Answer: 3 and 1 i think
Explanation: try to answer useing my answer or use google or bling