What does it mean to clean up a power plant?

Calculate the change in entropy if br2(l) is converted to br2(g). s° for br2(l) = 152.2 j/(mol•k) s° for br2(g) = 245.5 j/(mol•k) s° for br(g) = 175.0 j/(mol•k)

Sum of brother and sisters age is 26. four times the brothers age is subtracted from three times the sisters age, the difference is 8. what are the ages of the brother and sister?

Aman applies a force of 500n to push a truck 100m down the street how much does he do?