Answer:
Rock D.
Step-by-step explanation:
We can assume that the force that the catapult does is always the same.
So, here we need to remember Newton's second law:
F = m*a
force equals mass times acceleration.
Where acceleration is the rate of change of the velocity.
So, if we want the rock to hit closer to the catapult, the rock must be less accelerated than rock B.
So, we can rewrite:
a = F/m
So, as larger is the mass of the rock, smaller will be the acceleration of the rock after it leaves the catapult (because the mass is in the denominator). So if we want to have a smaller acceleration, we need to choose a rock with a larger mass than rock B.
Assuming that the mass depends on the size, the only one that has a mass larger than rock B is rock D.
So we can assume that rock D is the correct option.
Answer:
16.67% increase
Step-by-step explanation:
finding the percentage price increase
we need to find the difference in percentage price between the 2 years
12%-10% = 2%
2%/12% x 100% = 100%/6 = 16.67%
20% increase between January 1st 2010 and January 1st 2011
Answer:
Randomized experiment
Step-by-step explanation:
Such a statement is said to be Randomized experiment as the kids in the school have been selected at random and their performances are observed and recorded. Later it is inquired if they are breast fed or not. This information is later assessed and a conclusion is reached. This type of research or experiment is Randomized experiment.
Considering that the experiment is Randomized, the statement should be "Link found between breast-feeding and school performances". This statement does not restrict the performances of the student specifically on breast-feeding but shows a probable affect of it.
A U B = {1, 2, 3, 4, 5, 6, 7}
Step-by-step explanation:
- Step 1: Find A U B. Union of two sets A and B are the set of all elements in set A and set B.
A = {1, 2, 5, 7} and B = {3, 4, 6, 7}
A U B = {1, 2, 3, 4, 5, 6, 7}