How are families different now than they were in earlier times?
many families are (blank) materialistic now than they were earlier.
a) more
b) less
c) as
they also tend to be (blank) close-knit as compared to families from earlier times.
a) more
b) less
c) as
(blank) has also become significant in the modern world.
a) family learning
b) cultural learning
c) formal education

Explanation:

1 A, many families are more materialistic now than they were earlier, and it's directly related to how the world economy has been evolving.

2 B. They tend to be less close-knit as compared to families from earlier times, because nowadays, the culture of quickness and short lasting bonds is taking over, so human relationships are less deep than before.

3 C. Formal Education has became significant in this modern world, because children don't study to learn, they study to pass the exams and get high marks in order to be considered in the future.

ek = (m·v2) / 2

v - velocity of system after the collision

m = m1 + m2

ek = (m1 + m2) ·v2/2

ek = (200 + 250) ·2,32/2 = 450·5,29/2 = 1190,25 j