Answer:
B and F
Step-by-step explanation:
The fourth quadrant contains a positive number for the x axis and a negative number for the y axis. (B=4,-5 and F=4,-7)
I'll proceed by evaluating total length and surface area by scanned images. For measurements, I suggest to use winrhizo or any similar software. In this case the most important thing to think about is to use the appropiate acquisition parameters, I mean, to set a good resolution during scanning. Pixels of the aquired image should be smaller than root hairs diameter. Therefore, let me try to suggest you a good acquisition resolution. Making a quick research, it seems that hair root diameters range between 0,012 and 0,017 mm, so I suggest a resolution that will give a pixel dimension of 0,002 mm. Root hair diameters should be composed by 6-8 pixels, that is enough for winrhizo measurements. Resolution is measured in dpi, so in "dots/pixel per inch". A inch is 25,4 mm. We need pixels with a diameter of 0,002 mm, so in 25,4 mm we found 12700 pixels. That means 12700 dpi. It's a very high resolution, you need a good scanner and much space in your computer.
Answer: First half was 24 minutes
Step-by-step explanation:
Let the time taken to finish the second half be y.
Since the student used 2/3 of the second half time to finish the first half, first half = 2/3 × y = 2y/3
The entire exam is an hour which equals 60 minutes
First half + Second half = 60minutes
Note that first half is denoted as 2y/3 and second half is denoted by y.
2y/3 + y = 60
5y/3 = 60
Cross multiply
5y = 60 × 3
5y = 180
y = 180/5
y = 36
Second half took 36 minutes
Since first half is 2y/3, it will be:
(2×36) / 3
= 72/3
= 24minutes
First half took 24 minutes.
Any portion of the circumference of a circle is called a radius