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Ronch [10]
3 years ago
10

A chemistry teacher is able to grade chemistry labs at a rate of 5 labs for every 3 minutes. They need to grade 165 labs how man

y hours will it take?​
Chemistry
1 answer:
PIT_PIT [208]3 years ago
3 0

Answer:

1.65hr

Explanation:

Given parameters:

Number of labs  = 5 labs

 Time taken  = 3 minutes

Unknown:

Time taken in hours to grade 165 labs  = ?

Solution:

Let us find the rate of the teacher;

  Rate  = \frac{number of labs}{time}  

  Insert the parameters and solve;

   Rate  = \frac{5}{3}   = 1.67labs/min

Now;

   Time to grade 165 labs  = \frac{number of labs}{rate}  

   Time to grade 165 labs  = \frac{165}{1.67}   = 98.8min

  Since;

               60min = 1hr

               98.8min  = \frac{98.8}{60}   = 1.65hr

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That means generally, the greater the electronegativity difference between two atoms is, the shorter you can expect the bond to be, insofar as the electronegative atom is the same size as another comparable electronegative atom.
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