Answer:
This question is incomplete, it is asking to identify the following variables in the question:
Independent Variable: DIFFERENT AMOUNTS OF OIL
Dependent Variables: NUMBER OF KERNELS THAT POPPED
Controlled Variables: TIME FOR POPPING, SAME BRAND OF KERNEL, SAME COOKING TIME
Explanation:
The independent variable of an experiment refers to the variable that the experimenter intentionally manipulates or changes for the purpose of effecting a measurable response in another variable (dependent variable). In this experiment, the independent variable is DIFFERENT AMOUNTS OF OIL used because this is what Jason changes in the experiment.
Contrarily, the dependent variable is the variable that the experimenter measures in response to the independent variable. In this experiment, Jason measures the NUMBER OF KERNELS THAT POPPED from using different amounts of oil. Hence, the NUMBER OF KERNELS THAT POPPED is the dependent variable.
Controlled variables or constants are those variables that must be kept constant or unchanged throughout the experiment in order not to influence the findings of the experiment. In this case, the following variables were kept constant for all the groups: TIME FOR POPPING , SAME BRAND OF KERNEL (Pop rite), SAME COOKING TIME (4 mins).
Controlled population growth.
Explanation:
US is a highly developed country and it has expansive infrastructure and highly mechanized agricultural equipments. So first option is not a choice. Second, access to chemical fertilizers and pesticides in a country with such advanced agriculture infrastructure is very easy. Third US is well known for using GM crops.
US does not have a controlled population growth because if not the birth rate then migration of people to US is a major concern for that country. Thus, this will be a correct choice for the given question.
<span><span>Radio waves: If our eyes could see radio waves, we could (in theory) watch TV programs just by staring at the sky! Well not really, but it's a nice idea. Typical size: 30cm–500m. Radio waves cover a huge band of frequencies, and their wavelengths vary from tens of centimeters for high-frequency waves to hundreds of meters (the length of an athletics track) for lower-frequency ones. That's simply because any electromagnetic wave longer than a microwave is called a radio wave.</span><span>Microwaves: Obviously used for cooking in microwave ovens, but also for transmitting information in radar equipment. Microwaves are like short-wavelength radio waves. Typical size: 15cm (the length of a pencil).</span><span>Infrared: Just beyond the reddest light we can see, with a slightly shorter frequency, there's a kind of invisible "hot light" called infrared. Although we can't see it, we can feel it warming our skin when it hits our face—it's what we think of as radiated heat. If, like rattlesnakes, we could see infrared radiation, it would be a bit like having night-vision lenses built into our heads. Typical size: 0.01mm (the length of a cell).</span><span>Visible light: The light we can actually see is just a tiny slice in the middle of the spectrum.</span><span>Ultraviolet: This is a kind of blue-ish light just beyond the highest-frequency violet light our eyes can detect. The Sun transmits powerful ultraviolet radiation that we can't see: that's why you can get sunburned even when you're swimming in the sea or on cloudy days—and why sunscreen is so important. Typical size: 500 nanometers (the width of a typical bacteria).</span><span>X rays: A very useful type of high-energy wave widely used in medicine and security. Find out more in our main article on X rays. Typical size: 0.1 nanometers (the width of an atom).</span><span>Gamma rays: These are the most energetic and dangerous form of electromagnetic waves. Gamma rays are a type of harmful radiation. Typical size: 0.000001 nanometers (the width of an atomic nucleus).</span></span>
The answer is option 4 :3
