Which environment will you find a pirarucu?
a. tree canopy
b. river
c. forest floor
d. wetland

Geologists know that potassium-40 decays to argon-40, with a half-life of 1.3 billion years. if an analysis of a feldspar crystal in a sample of granite shows that 75 percent of the potassium-40 atoms have decayed to form argon-40, what is the age of the granite

Paraguay is one of the only two countries in the americas that don't have a coastal border. the country is slightly smaller than california. it was under a military dictatorship for 35 years, ending in 1989; today it is a constitutional republic. most of the population is roman catholic, and over 60% of the people live in cities. its environment is threatened by deforestation and water pollution. which of the following facts from the paragraph above best describes an element of paraguay's culture? (apex)

Which of the following is a measure of the amount of light a star directly emits? a. luminosity b. wavelength c. brightness d. intensity