Answer:
B
Explanation:
Crossing over is the process involved during meiosis of two chromosomes sharing genetic information with each other from each parent. This happens so the two daughter cells or sister chromatids have a variety of genetic information and so they are not completely identical. This leads to genetic diversity or variation.
Answer:
The answer is A. Fertilized ovules
Answer:

Explanation:
First, let's identify the tools needed.
Since the biology class is studying the temperature, they will likely need a <u>thermometer</u>. Also, they are gathering information about the growth of the plants. This could use a <u>balance </u>of a meterstick.
Next, recall the difference between quantitative and qualitative data.
- <u>Quantitative</u>: Measurable and numerical results found using scientific instruments/devices
- <u>Qualitative</u>: Data found using the senses, such as descriptions and diagrams.
Since the class is measuring temperature and growth using tools, it must be quantitative data.
We can eliminate choices A and B, because they claim the class will gather qualitative data. Then, we can eliminate choice D, because a beaker and timer won't help with temperature and growth. That leaves choice C as the correct answer.
The right answer is 28 years.
The half-life, or period of a radioactive isotope, is the time required for half of the nuclei of this isotope initially present to decay naturally.
One gram of pure 90 strontium has a radioactivity of 5.11 TBq. Its beta radiation is not penetrating, which makes it difficult to measure when it is in the soil or a matrix. It is very harmful when the particle is inhaled or ingested.