C) Is the correct answer I believe, unless you want to flush the chemicals down the sink and then have a reaction with them the next time you go swimming in a lake and find them there.
Answer:
The article revealed the fact that Black inventors have always played an active role in inventing new things in America. In the 18th and 19th centuries they were denied the right to patent their inventions because of their status as slaves. This has changed for the better in present times as many Black inventors are being granted patent rights.
Explanation:
The article, "America’s always had black inventors – even when the patent system explicitly excluded them", by Shontavia Johnson, explained the active role that Black Americans, both free and slaves played in inventing things in the United Slaves. The article explained that although the patent rights signed into the constitution in 1787 was written in a neutral tone, it did not change the fact that black inventors were actually denied patent rights.
This segregation affected people like Henry Boyd, Ned, Benjamin Montgomery among others. In recent times, this segregation has significantly been curbed as many Black inventors are now owners of patents. An example is Lonnie Johnson, inventor of the Water Gun and owner of more than 80 patents.
Answer:
Independent variable - time. Dependent variable - the distance moved by the bubble along the capillary tube. Control variables - temperature, air flow or draughts, adequate supply of water.
