Answer:
<h2>Because water can lose and accept H + ions .......</h2>
The correct option is <u>D</u>.
Qualitative observations are observations that are made using our senses of sight, hearing, smell, taste and feel. These observations do not involve numbers or measurements of any kind.
The student's observations regarding the squirrel as is mentioned in options A, B and C involve measurements. Therefore these are not qualitative observations.
Option D, however, is made on the basis of sight, where the student observes the squirrel moving in a zigzag manner.
Therefore, of all the three observations, the student's observation that the squirrel ran in a zigzag pattern is the qualitative observation.
The answer is E. Short and thick while cold.
Answer:
d = 2,042 10-3 m
Explanation:
The laser diffracts in the circular slit, so the process equation is
d sin θ= m λ
The first diffraction minimum occurs for m = 1
We can use trigonometry in the mirror
tan θ = Y / L
Where L is the distance from the Moon to Earth
Since the angle is extremely small
tan θ = sin θ / cos θ
Cos θ = 1
tant θ = sin θ = y / L
We replace
d y / L = λ
d = λ L / y
Let's calculate
d = 532 10⁻⁹ 3.84 10⁶/1 10³
d = 2,042 10-3 m
No force contributes to density, the density is a physical quantity that is defined as being

the raport between the mass of the object and its volume. However if you want to measure the density of an object you might want to determine its gravity force (weight)

from which knowing the gravitational acceleratin you can find its mass
where

is given in Newtons and

is given in