#3 answer: 42
3x7= 21
21x2=42
#4 answer:140
5x7=35
2x2=4
4x35=140
Last one!
explanation is I remember having this question and studying this bad in middle school :)
For a more see orthocenter of a triangle .The orthocenter is the point where all three altitude of the triangle intersect. An altitude is a line which passes through a vertex of the triangle and is a perpendicular to the opposite side. Hope this helps :)
Answer: 
Step-by-step explanation:
Let "x" represents the 16% of 43 minutes.
Once you analize the information given in the exercise, you can identify that 43 minutes is the 100%.
Then, with this data, you can set up the following proportion:

Now you must solve for "x". The steps are:
- Multiply both sides of the equation by "x"

- Multiply both sides by 43:

- Divide both sides by 100:

- Rounding to the tenths place:

Answer:
0.48 of the room per hour
Step-by-step explanation:
your welcome