Generally speaking, negative ions increase the flow of oxygen to the brain resulting in higher alertness, decreased drowsiness, and more mental energy.
Answer:
d. the same within the uncertainty of each measurement method
Explanation:
The density of an object and in general any physical property, has the same value regardless of the method used to measure it, either directly or indirectly. Since two completely different valid methods are used, the results must be the same, taking into account the level of precision of each of the methods.
Answer:
<em>Toasties are British in origin and were usually made in ovens. They were the same as a grilled cheese but the bread was not buttered. Some Brits would make them in a pan in the oven, too, which is even closer to the stove-top grilled cheese.</em>
Answer: 56994 miles
Explanation:
Given : Toby's Trucking Company determined that on an annual basis, the distance traveled per truck is normally distributed with

Standard deviation : 
Let a be the distance traveled by at least 72% of the trucks.
Let X be the random variable that represents the distance traveled by a truck
Then 
The critical value corresponds to p-value 0.72 :
Also, 

Hence, 56994 miles will be traveled by at least (equal to and more than) 72% of the trucks .
Answer:
Explanation:
Given
mass of ice 
Final temperature of liquid 
Specific heat of water 
Latent heat of fusion 
Latent heat of vaporization 
Suppose M is the mass of steam at 
Heat required to melt ice and convert it to water at 

Heat released by steam

and
must be equal as the heat gained by ice is equal to Heat released by steam


![\Rightarrow M=\dfrac{m[L+c\times T_f]}{L_v+c(100-T_f)}](https://tex.z-dn.net/?f=%5CRightarrow%20M%3D%5Cdfrac%7Bm%5BL%2Bc%5Ctimes%20T_f%5D%7D%7BL_v%2Bc%28100-T_f%29%7D)
![\Rightarrow M=\dfrac{119[333\times 10^3+4186\times 57]}{2256\times 10^3+4186\times (100-57)}](https://tex.z-dn.net/?f=%5CRightarrow%20M%3D%5Cdfrac%7B119%5B333%5Ctimes%2010%5E3%2B4186%5Ctimes%2057%5D%7D%7B2256%5Ctimes%2010%5E3%2B4186%5Ctimes%20%28100-57%29%7D)

