BNL Essay essays

BNL Essay essays Barenaked Ladies Biographical Essay The Canadian band, Barenaked Ladies, has sold 500,000 copies of their well known album, Gordon. Scarborough, Ontario's The Barenaked Ladies started in 1988 as the duo of Page and Robertson who had previously played together in a Rush clone band. They released a cheap cassette called Buck Naked' in 1989 followed by 1990's 'Barenaked Lunch' which was the Creeggan brothers debut. By 1991 Tyler Steward had joined the band and the group was stirring up publicity both with their savage wit and impromptu acoustic concerts (especially on live radio) but in the media by being banned by Toronto mayor June Rowlands who wouldn't allow them to play in Nathan Phillips Square due to their 'offensive' name. Barenaked Ladies have a very diverse group with a more diverse array of songs, there are many, many huge singles that have been let out by this amazing band. Their first big single was If I Had A Million Dollars, which made its debut in 1992. The song is categorized as a comical fantasy song. There are many different versions of this song. There are solo acoustic versions, live versions, and many more. There are different versions of this song so that the artist can give different feeling and renditions to the melody, an acoustic guitar holds a more mellow melody. While live versions hold more of a jumpy melody. Their overall most popular song was not just one single, it was the entire Gordon album. The Gordon album sold well over 500,000 copies. The album incorporates many genres of music. There are contemporary, pop, rock, and soothing songs. Gordon is the epitome of all the great BNL songs. In 1992, The Record, which is a Canadian album Chart hits company ranked Gordon as #1 in the year of 1992. That shows the magnitude and popularity of the Barenaked Ladies in their home country. Barenaked Ladies are very generous as well. They contributed over 3 mil ...

What Half Life Means for Evolution

What Half Life Means for Evolution Perhaps the most widely used evidence for the theory of evolution through natural selection is the fossil record. The fossil record may be incomplete and may never fully completed, but there are still many clues to evolution and how it happens within the fossil record. One way that helps scientists place fossils into the correct era on the geologic time scale is by using radiometric dating. Also called absolute dating, scientists use the decay of radioactive elements within the fossils or the rocks around the fossils to determine the age of the organism that was preserved. This technique relies on the property of half-life. What Is Half-Life? Half-life is defined as the time it takes for one-half of a radioactive element to decay into a daughter isotope. As radioactive isotopes of elements decay, they lose their radioactivity and become a brand new element known as a daughter isotope. By measuring the ratio of the amount of the original radioactive element to the daughter isotope, scientists can determine how many half-lives the element has undergone and from there can figure out the absolute age of the sample. The half-lives of several radioactive isotopes are known and are used often to figure out the age of newly found fossils. Different isotopes have different half-lives and sometimes more than one present isotope can be used to get an even more specific age of a fossil. Below is a chart of commonly used radiometric isotopes, their half-lives, and the daughter isotopes they decay into. Example of How to Use Half-Life Lets say you found a fossil you think to be a human skeleton. The best radioactive element to use to date human fossils is Carbon-14. There are several reasons why, but the main reasons is that Carbon-14 is a naturally occurring isotope in all forms of life and its half-life is about 5730 years, so we are able to use it to date more recent forms of life relative to the geologic time scale. You would need to have access to scientific instruments at this point that could measure the amount of radioactivity in the sample, so off to the lab we go! After you prepare your sample and put it into the machine, your readout says you have approximately 75% Nitrogen-14 and 25% Carbon-14. Now it is time to put those math skills to good use. At one half-life, you would have approximately 50% Carbon-14 and 50% Nitrogen-14. In other words, half (50%) of the Carbon-14 you started with has decayed into the daughter isotope Nitrogen-14. However, your readout from your radioactivity measuring instrument says you have only 25% Carbon-14 and 75% Nitrogen-14, so your fossil must have been through more than one half-life. After two half-lives, another half of your leftover Carbon-14 would have decayed into Nitrogen-14. Half of 50% is 25%, so you would have 25% Carbon-14 and 75% Nitrogen-14. This is what your readout said, so your fossil has undergone two half-lives. Now that you know how many half-lives have passed for your fossil, you need to multiply your number of half-lives by how many years are in one half-life. This gives you an age of 2 x 5730 11,460 years. Your fossil is of an organism (maybe human) that died 11,460 years ago. Commonly Used Radioactive Isotopes Parent Isotope Half-Life Daughter Isotope Carbon-14 5730 yrs. Nitrogen-14 Potassium-40 1.26 billion yrs. Argon-40 Thorium-230 75,000 yrs. Radium-226 Uranium-235 700,000 million yrs. Lead-207 Uranium-238 4.5 billion yrs. Lead-206