After two half-lives or 60 years, 7.5 g of the element will be left.
<u>Explanation:</u>
<u>Half-life:</u>
- In simple words, Half-life can be defined as the amount of time needed for a quantity to fall to half its value as contained at the beginning of the time period.
- In this problem the half-life of the element is thirty years, then after thirty years half of the sample would have decayed and half would be left as it is.
- After thirty years (The first half-life ) 30 /2 = 15 g declines and 15 g remains disappeared.
- And after another sixty years (The two half-lives) 15 /2 = 7.5 g declines and 7.5 g remains disappeared.
- After two half-lives or 60 years, 7.5 g of the element will be left.
The question is incomplete. The complete question is:
Question: A gene for corn has two alleles, one for yellow kernels and one for white kernels. Cross pollination of yellow corn and white corn results in ears of corn that have an approximately even mix of yellow and white kernels. Which term best describes the relationship between the two alleles?
a) Incomplete dominance
b) Genetic recombination
c) Chimerism
d) Codominance
Answer:
d) codominance
Explanation:
Codominance is a pattern of inheritance when none of the alleles of a gene is able to mask the expression of the other allele of the same gene. When the two alleles are present together in a heterozygous genotype, both are expressed and the phenotype of the heterozygote is different from both the pure breeding parents. In the given example, cross-pollination of yellow corn and white corn results in the ears of corn that have an approximately even mix of yellow and white kernels. This means that the heterozygote expresses both the allele for the corn color. Therefore, it represents codominance.
Answer:
Protons, neutrons, and electrons: Both protons and neutrons have a mass of 1 amu and are found in the nucleus. However, protons have a charge of +1, and neutrons are uncharged. Electrons have a mass of approximately 0 amu, orbit the nucleus, and have a charge of -1.
Explanation: