Answer: i think c
Explanation:QA: “What is ordinary glass made of ?”
Glass is mostly silica, or silicon dioxide, present as quartz in many types of sand. Pure silica forms a highly transparent glass, but has a very high melting or softening temperature, around 1700°C. Even at such high temperatures it is highly viscous and difficult to work. Its use is largely confined to applications requiring high transparency to ultra-violet and infra-red radiation, stability at elevated temperatures or low thermal expansion coefficient.
“Ordinary glass” windows and drinking vessels are typically made from soda-lime glass, containing silica with around 25% sodium, calcium and other oxides, which together reduce the softening temperature to roughly 500–600°C
A surface wave is a wave in which particles of the medium undergo a circular motion.
Verrrrrry interesting !
Acceleration = (change in speed) / (time for the change)
The car's acceleration is (60 mph) / (3.8 sec) = (60/3.8) mile/hr-sec .
Final speed = (original speed) + (acceleration · time)
= (30 mi/hr) + (60/3.8 mi/hr-sec)·(6 sec)
= (30)mi/hr + (360 / 3.8)mi/hr
= 124.7 mph .
