Answer:
8923 years
Step-by-step explanation:
Half life of C-14 = 5730yrs
decay rate= 34%
Halt life (t^1/2) = (ln2) / k
5730 = (ln2) /k
k = (ln2) / 5730
k = 1.209 * 10^-4
For first order reaction in radioactivity,
ln(initial amount) = -kt
ln(34/100) = -(1.209*10^-4)t
-1.0788 = -(1.209*10^-4)t
t = -1.7088/ -1.209*10^-4
t = 8923 years
The answers to the blanks are
1. 600,
2. 120,
3. 120,
4. 180.
Explanation:
- The fence means perimeter around the court. So a tennis court's perimeter is 600 feet fence. The perimeter of a rectangle is 2 times the sum of the rectangle's length and the rectangle's width.
- It is given that length equals 60 more than width i.e. l = w + 60, where l is the length of the court and w is the width of the court.
- The perimeter of a court = 600 = 2 (l + w) = 2l + 2w = 2 (w +60) + 2w, this becomes, 2w + 120 + 2w = 600; 4w = 480, w = 120.
- Since l = w + 60, l = 120 + 60 = 180. So length of a court is 180 feet and the width of a court is 120 feet.
It's c.
for example:
2*2 +1 = 5
2*4 +1 =9
you can keep going ....
Answer:
34
Step-by-step explanation:
the equation is 2(lw+lh+wh)
2( 1.5 x 2 + 1.5 x 4 + 2 x 4)
