I notice that even though we're working with frames of reference
here, you never said which frame the '5 km/hr' is measured in.
In fact ! You didn't even say which frame the '12 km/hr' of his
bike is measured in.
So there are several different ways this could go. I'll do it the way
I THINK you meant it, but that doesn't guarantee anything.
-- Simon is riding his bike at 12 km/hr relative to the sidewalk,
away from Keesha.
-- He throws a ball at Keesha, at 5 km/hr relative to his own face.
-- Keesha sees the ball approaching her at (12 - 5) = 7 km/hr
relative to the ground and to her.
Ca(NO3)2(aq) + Na2CO3(aq) → 2NaNO3 + CaCO3⬇. NaNO3 is solution so CaCO3 is the precipitate formed.
Answer:
alcohol thermometer is preferred for a very cold region. Alcohol thermometer is preferred for a very cold region because its freezing point of alcohol is - 117°C. So, it can measure the temperature of the very cold region.
Answer:
<em>About four million tons of </em><em><u>matter</u></em><em> are converted to energy in the Sun’s core every second</em>
Explanation:
<u>The Sun
</u>
It's estimated that The Sun fuses near 600 million tons
of hydrogen into helium every second. As a result, 4 million tons of matter are converted to energy every second according to Einstein's equation 
Environmental Protection Agency enforced regulations primarily aim to reduce environmental pesticide contamination.
<h3>What is a Pesticide?</h3>
This refers to a chemical which is used to control pests and examples include insecticide, nematicide etc.
Environmental Protection Agency is government owned and ensures strict enforcement of regulations to reduce environmental pesticide contamination which could lead to death of beneficial organisms.
Read more about Environmental Protection Agency here brainly.com/question/23486143
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