The factors that are needed to be controlled are :
1. the date of manufacturing of the drug should be the same
2. the amount of drug should be the same
3. the time they will take the drug should be the same
4. the food they are taking should be the same
5. the activities they are doing should be the same
Answer: 
Step-by-step explanation:
To solve for y, we want to isolate y.
[multiply both sides by y]
[subtract both sides by 3y]
[factor out y]
[divide both sides by (w-3)]

Now, we know that
.
Answer: 120 beats per 45 seconds
Step-by-step explanation:
Answer: The answer is D
Step-by-step explanation:
I used desmos graphing calculator! Look it up it really helps! Literally gives the answers. :)
Perimeter is l+l+w+w, or l*2+w*2. We know the width is 4 feet. 26=4*2+l*2
So first, find what 4*2 equals. The answer is 8. So subtract 8 from both sides. 4*2 Cancels out, and 26 changes to 18. Then, divide both sides by 2. The (*2) gets cancelled and 18 becomes 9. The length is 9 FEET.
:)-Kibeye