Answer:

Explanation:
From the question we are told that
Mass 
Height 
Generally the equation for velocity before impact is is is mathematically given by



Generally the equation for Kinetic Energy is is mathematically given by




I sort of understand but what does it mean by.... Another?
Answer:
The difference is 7.6 grams.
Explanation:
In mathematics the difference of two numbers is express as the subtraction between them:

So to find out the difference between the two measured masses, a will be represented by 123.6 grams since is the bigger number, and b by 115.972 grams.
Therefore, it is get:

<u>Hence, the difference is 7.6 grams. </u>
The result of 7.628 will be expressed as 7.6 to have the correct number of significant figures.
Notice how that can be express in units of kilograms too since there is 1000 gram in 1 kilogram:
⇒ 
Answer:
0.7 hours
Explanation:
From the way back, we can calculate the distance between Irina's work and Irina's home. In fact, we know that the car takes 0.4 hourse traveling at 27 mph, so the distance covered should be

When Irina rides to work with her bike, she travels at a speed of 16 mph. So we can find the time she takes by dividing the total distance (10.8 miles) by her speed:
