Answer:
b. experiment
Step-by-step explanation:
An observational study is one in which the researchers monitor the effect of a risk factor on subjects without introducing interventions for the purpose of noting differences in results. An experiment is mainly a randomized control trial where subjects are assigned to groups and chosen by chance. Interventions are also introduced by the researchers so as to note the different possible results within the groups and among participants.
The above-described process incorporates an experiment and that is why the researchers introduce protein level diet as interventions. It also employs the random assignment of subjects to different groups so as to improve the accuracy of the process.
The number of bananas required to make the third scale balance is 3.
<h3>What is a scale?</h3>
A scale is a tool used for weighting objects. If the objects on each side weigh the same the scale is balanced. Based on this, let's determine the possible weight of each fruit to balance the last scale.
- Scale 1 (10 bananas/ 2 pineapples)
It is known 10 bananas weigh as much as 2 apples, but to solve this problem let's assume 10 bananas weigh a total of 1000 grams.
- 10 banans = 1000 grams = each banana weighs 100 grams
- 2 pineapples = 1000 grams = each pineapple weighs 500 grams
Scale 2 ( 1 pineapple / 2 bananas, 1 apple)
Using the same imaginary weights let's find the weight of the apple.
- 1 pineapple = 500 grams
- 2 bananas = 200 grams
- 1 apple = 300 grams (500 - 200 = 300)
Scale 3 (1 apple /x )
We know 1 apple is equal to 300 grams and 1 banana is equal to 100 grams. Based on this, the number of bananas to balance the scale is 3.
Learn more about balance in: brainly.com/question/7181548
Answer:
d
Step-by-step explanation:
i know it's rhe right answer
x = -10 that is the answer your welcome
Simplify using FOIL 15x3+18x+10x2+12