What was the primary motivation for the drawing of lake beds in Mexico City ?
A to reduce the risk of fooding
B to prevent the spread of diseases
C to protect the city from invaders
D omine for gold under the lake beds

What is the result of the greenhouse effect? a. heat is deflected from the atmosphere. b. heat is released from the atmosphere. c. heat is kept in the atmosphere. d. plants are able to grow in the tropics where the air is the heaviest.

What weather system might be occurring if the pressure gradient decreases and fish harvests in peru are weaker than normal

Some gamma ray bursts are hypothesized to come from mergers of neutron stars or black holes. if this hypothesis is correct, what else should we in principle be able to detect from such mergers? a. gravitiational waves b. x-ray bursts c. significant disruption of gas thousands of light-years away in the surrounding galaxy d. an "afterglow" of bright visible light, lasting for weeks