Why do many species that existed 35 million years ago no longer exist

Which of the following are considered noble gases? a. bromine b. neon c. argon d. chlorine

What is the temperature in degrees celsius of a substance with a tempature of 49k

An object with initial temperature 130 ∘ f is submerged in large tank of water whose temperature is 50 ∘ f . find a formula for f ( t ) , the temperature of the object after t minutes, if the cooling constant is k = − 0.2 . remember newton's law of cooling (the rate of change of temperature with respect to time is equal to k times the difference between the temperature of the object and the surrounding temperature) ! : )