Note that 8.00 = (2.00)^3, that implies that a decay to 1/8.00 means that the Carbon-14 has passed 3 half-life. (1 to decay to 1/2, other to decay to 1/4, and other to decay to 1/8). And, three half-life is 3 * 5730 years = 17,920 years. So,<span> the answer is that the plant was alive 17,920 years.</span>

7 0

3 years ago

Solve the system of equations<br> 3x+4y+12<br> 9x-2y=15

Mrrafil [7]

3x+4y=12
9x-2y=15
we will use elimination
multiply 3x+4y=12 by -3

-9x-12y=-36
9x-2y=15
_________ add
-14y=-21
÷-14 both sides
y=1.5
find x
3x+4 (1.5)=12
3x+6=12
-6 both sides
3x=6
÷3 both sides
x=2

x=2
y=1.5

3 0

3 years ago

6 Petra wants to buy an electronic reader that costs $160.75 including tax. She has saved $34.75 SO

nalin [4]

Answer:

Petra would need to save for 12 weeks to get 126

126+34.75=160.75

7 0

2 years ago

Mr. Black is flying a kite above a field on a 65 foot string. The angle of elevation of the kite is 70 degrees. How high is the

Elan Coil [88]

Answer:

The correct answer is 61.08 foot.

Step-by-step explanation:

Length of the string of the kite, Mr. Black is flying is 65 foot. Thus the length between the kite and Mr. Black is given by 65 foot.

Angle of elevation is 70°.

We need to calculate the height of the kite above Mr. Black's head. The height is given by finding the sine of the angle of elevation.

Let the height be x foot.

Thus sin 70° = $\frac{x}{65}$

⇒ x = sin 70° × 65

⇒ x = 61.08

Thus the height of the kite above Mr. Black head is 61.08 foot.

6 0

3 years ago