A student performed an experiment in which 10 mL of a strong acid was placed on a sample of limestone. Bubbles formed where the acid touched the limestone. After 20 minutes, the bubbling stopped and the surface of the limestone appeared unchanged. What is an observation that suggests a chemical reaction did in fact take place between the acid and the limestone? a) The limestone appeared to be unchanged.
b) The acid had to be prepared beforehand.
c) Bubbles formed where the acid and limestone touched.
d) None of the above

smooth muscle is composed of involuntary muscles found within the walls of organs and structures such as the esophagus, stomach, intestines, and blood vessels. those muscles push materials like food or blood through organs. unlike skeletal muscle, smooth muscle can never be under your control.

c (diamond),

sio2 (quartz)

they it depends on if one believes about radioactivity, they make a geiger counter beep but maybe it was going to beep anyway electronics do wierd things all the time or it was programmed to beep near certain metals.

the answer is c i took the test