Answer:
A: ≤ means less than OR equal to. < only means less than
B: 9
Explanation:
A: Because it would equal 19, and 19 is EQUAL than 19. 4(5) - 1 would equal 19, which is equal to 19, and not less than. ≤ means less than or equal to. < means less than. So its not true.
B: 47 - 2, 45. Then 5 x 9 equals 45. So 5 x 9 equals 45, then add 2 would equal 47.
Hope this helps <3
Answer:
h2 = 0.092m
Explanation:
From a balance of energy from point A to point B, we get speed before the collision:
Solving for Vb:

Since the collision is elastic, we now that velocity of bead 1 after the collision is given by:

Now, by doing another balance of energy from the instant after the collision, to the point where bead 1 stops, we get the distance it rises:
Solving for h2:
h2 = 0.092m
The resultant displacement between the two vectors will increase.
The resultant of the two vectors is given by parallelogram law of vectors.
The parallelogram law of vector addition states that if two vectors are represented in magnitude and direction by the adjacent sides of a parallelogram, the diagonal of the parallelogram drawn from the point of intersection of the vectors represents the resultant vector in magnitude and direction.
The resultant of these vectors, say vector A, and B, is given as;

When;
θ = 90°

When;
θ = 120°

Thus, the resultant displacement between the two vectors will increase.
Learn more here: brainly.com/question/20885836
I think its b too but i may be wrong
They do the method 3 times to be sure. Because if you do it once, that could mean anything. If you do it twice, it may or may not have the same result. If you do it 3 times and it matches one of the previous answers, then it's likely that it's correct.