66 mph
Explanation:
Average speed is the rate of change of distance with time:
Average speed = 
Given parameters:
Starting point = 88mile marker
End of journey = 121mile marker
time = 30minutes = 0.5hr(60min = 1hr)
Solution:
The distance covered in this journey:
Distance = End of journey - starting point = 121 mile - 88 mile = 33mile
Average speed = 
= 66mph
The average speed of Sara's mum is 66mph
Learn more:
Average speed brainly.com/question/8893949
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Answer:
What is the charge of CA?
2+
Table of Common Element Charges
Number Element Charge
17 chlorine 1-
18 argon 0
19 potassium 1+
20 calcium 2+
88 more rows•Dec 24, 2018
The compound sodium carbonate is a strong electrolyte because it completely dissociates when placed in water into its component ions. The equation of the reaction can be expressed as:

The dissociation leads to the formation of sodium and carbonate ions with the latter held together by its internal covalent bond.
This is unlike weak electrolytes that do not dissociate completely in water or aqueous solutions. Only a small fraction of the solute exists as ions in the solution.
More on strong and weak electrolytes can be found here: brainly.com/question/3410548
Could you please retake the picture
Answer:
Just add a plenty of dots in the first one and very few dots in the second one