3 years ago

Anyone I’m really lost

Mathematics

1 answer:

Savatey [412]3 years ago

3 0

Answer:

The answer is option 3.

Step-by-step explanation:

You have to substitute H+=2×10^(-9) into the equation of pH :

pH = -log[H+]

H+ = 2×10^(-9)

pH = -log[2×10^-9]

= 8.70 (3s.f)

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2 years ago

recent survey found that 71% of all adults over 50 wear glasses for driving. In a random sample of 30 adults over 50, what is

valentina_108 [34]

Answer:

Mean = 21.3

Standard Deviation = 2.48

Step-by-step explanation:

We are given the following in the question:

p = 71% = 0.71

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5 0

3 years ago

Chocolate bars come in packs of 8 and graham crackers come in packs of 12. What is the smallest number of chocolate bars and g

Solnce55 [7]

Answer:

3 chocolate bars, and 2 graham crackers

Someone forgot the marshmallows...... :P

Step-by-step explanation:

Chocolate bars = 8 pack

Graham Crackers = 12pack

To have no crackers or chocolate left over, we need to find LCM

Factors of 8:

8, 16, 24, 32, 40, 48, 56, 72....

Factors of 12:

12, 24, 36, 48, 60, 72

The smallest LCM is 24

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Graham Crackers:

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If my answer is incorrect, pls correct me!

If you like my answer and explanation, mark me as brainliest!

-Chetan K

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3 years ago

Read 2 more answers

!!! I NEED HELP ASAP!!! Please can you help me fill in this chart for 45-45-90 and 30-60-90 triangles I know how to do the first

Marina86 [1]

Answer:

u add 45 + 45 +90 that’s 180 and all triangles equal 180

Step-by-step explanation:

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3 years ago