D is the answer
(4+8)+1 = 13
4+(8+1) = 13
Therefore equation D is true
Answer:
3rd quadrant
Step-by-step explanation:
- First we just convert the angle from radians to degrees
- Now that's too big, all this means is if we start rotating from the positive y-axis in a circle we will cross the starting point 2 times, 2 full circles;
- Now in which quadrant it 210 degrees?
- 0 degrees to 90 degrees is 1st quadrant
- 90 degrees to 180 degrees is 2nd quadrant
- 180 degrees to 270 degrees is 3rd quadrant
- 270 degrees to 360 degrees is 4th quadrant
- So our answer is the 3rd quadrant.
Answer:
Amount of Niobium-91 initially
= 300/91 =3.2967mol
2040 years = 3 ×680 = 3 half-lives
therefore, amount left = 0.4121mol
mass of Niobium-91 remaining = 0.4121 ×91 =37.5g
Please give brainliest
Answer:
B 3x: 51 = 3x+24: 85
Step-by-step explanation:
Since the triangles are similar
PS PQ
------- = -----------
PT PR
Substitute the values in
3x 3x+24
------- = -----------
51 85
3x: 51 = 3x+24: 85
He took 36 weeks to compose 12 songs.
Unit rate : Divide total weeks by total songs:
Unit Rate = 36 / 12 = 3 weeks per song.