A volcano that has not erupted in a very long time suddenly has a plume of steam coming from it. Which stages best describe this volcano? Check all that apply.

In a laboratory, nakisha mixes sodium hydroxide solution with an indicator called phenolphthalein. when combined, they create a pink solution. nakisha wonders if mixing other solutions with phenolphthalein will also create this pink color. how could she use the scientific inquiry process to explore it further?

Scientists use laser range-finding to measure the distance to the moon with great accuracy. a brief laser pulse is fired at the moon, then the time interval is measured until the "echo" is seen by a telescope. a laser beam spreads out as it travels because it diffracts through a circular exit as it leaves the laser. in order for the reflected light to be bright enough to detect, the laser spot on the moon must be no more than 1.0 km in diameter. staying within this diameter is accomplished by using a special large-diameter laser. part a if λ = 540nm , what is the minimum diameter of the circular opening from which the laser beam emerges? the earth-moon distance is 384,000 km. express your answer to two significant figures and include the appropriate units.

An initially unpolarized light if intensity 500 w/m^2 passes through four polarizers. the transmission axis between adjacent polarizers is 45∘. what percentage of the initial intensity is transmitted by the system?