Answer:
A) 277 million years
Step-by-step explanation:
Here, decay of U-238 is first order reaction. (since most of the nuclear decays are first order).
so, the equation t = 
× ln(
)
where, t = time from start of reaction
k = reaction constant
A(0) = initial concentration; A = present concentration.
⇒ 4.5 billion = 4500 million years = × ln2.
Now, given 95.82% of parent U-238 isotope is left.
⇒ t = × ln()
t = 
× ln(
)
⇒ t ≅ 277 million years.
#sol1
a1=1×4-1=3
a2=2×4-1=7
a3=3×4-1=11
a4=4×4-1=15
a5=5×5-1=19
#sol2
f(1)=1×4-1=3,
f(n+1)=f(n)+4,
so .... you know.
Answer: 78 pizzas
Step-by-step explanation:
65/10=6.5=10%
6.5*2=13 pizzas=20%
65+13=78 pizzas
Bookmark numbers helps keep track of how many bookmarks you have
Answer:
5
Step-by-step explanation:
Pythagoras's theorem dictates that a squared + b squared = c squared when talking about sides on right angled triangles with a and b being flat sides and c being the hypotenuse which gives us the forumula below
3 squared + 4 squared = 25 route 25 = 5
