Which of the following describes a response to external stimuli?

a boy sneezes when exposed to cat dander

a girl eats food when she is hungry

a child becomes hyperactive due to a chemical imbalance

a person yawns when oxygen levels in the blood are low

Which of the following true? a_volcanoes and earthquakes often near the plate boundaries. b_volcanoes occur whereve there are tall mountains. c_earthquakes cause volcanoes in the same location to erupt violently d_volcanoes and earthquakes occur only where plates are colliding with each other

Using data from seismic waves, geologists have learned that earth’s interior is made up of several

Which statement is true about hcl? (5 points) select one: a. it is a salt because it increases the concentration of metallic ions. b. it is a salt because it is formed by the reaction of an acid and a base. c. it is an acid because it increases the concentration of hydroxyl ions. d. it is an acid because it increases the concentration of hydronium ions.