Some scientists estimate that with the full use of plants' capabilities in feeding the world, the population could safely rise to billion.
a. 20
b. 50
c. 80
d. 100

Nebulae are enormous clouds in outer space. they are made mostly of hydrogen gas, helium gas, and dust. some nebulae glow brightly, while others do not. the stars that people see are huge, bright balls of glowing gas. they are made mostly of hydrogen and helium. which statement correctly describes other ways in which nebulae and stars are different? a. stars can form inside a nebula but a nebula can never be produced by any star. b. a star always has a higher density than a nebula. c. stars can never form inside a nebula but a nebula can be produced by any star. d. a nebula always has a higher density than a star.

Iron (fe) reacts with copper sulfate (cuso4) to form iron (ii) sulfate. in this reaction, cu2+ gains electrons to form cu. which statement is true about this reaction? fe(s) + cuso4(aq) → feso4(aq) + cu(s)

Mr. rose asked his student to draw a quadrilateral with four unequal sides. an example of this kind of quadrilateral